ionic liquids: prediction of melting point by molecular-based model

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Thermochimica Acta 549 (2012) 17– 34

Contents lists available at SciVerse ScienceDirect

Thermochimica Acta

jo ur n al homepage: www.elsev ier .com/ locate / tca

onic liquids: Prediction of melting point by molecular-based model

asrin Farahania, Farhad Gharagheizib,∗, Seyyed Alireza Mirkhanib, Kaniki Tumbac

Department of Chemistry, Buinzahra Branch, Islamic Azad University, Buinzahra, IranDepartment of Chemical Engineering, Buinzahra Branch, Islamic Azad University, Buinzahra, IranDepartment of Chemical Engineering, Mangosuthu University of Technology, Durban, South Africa

r t i c l e i n f o

rticle history:eceived 19 April 2012eceived in revised form 7 September 2012ccepted 7 September 2012vailable online 17 September 2012

eywords:elting point

onic liqudsSPR modelentic function approixmationescriptors

a b s t r a c t

The aim of is this study is to develop molecular-based model for prediction of melting points of diverseclasses of ionic liquids. For this purpose, exhaustive literature survey was conducted in order to col-lect comprehensive database of the melting points of ionic liquids. The melting points of 808 diverseionic liquids belongs to Sulfonium, Ammonium, Pyridinium, 1,3-Dialkyl imidazolium, Tri-alkyl imidaz-olium, Phosphonium, Pyrrolidinium, Double imidazolium, 1-Alkyl imidazolium, Piperidinium, Pyrroline,Oxazolidinium, Amino acids, Guanidinium, Morpholinium, Isoquinolinium and Tetra-alkyl imidazoliumhave been collected from 131 various references. Quantitative Structure–Property Relationship (QSPR)approach was applied in order to develop a reliable model for the prediction of the melting points ofionic liquids. As far as the authors concern, the investigated data has the broadest range of anion andcation structures among the previous studies which enhances its generality to predict melting point ofunknown ionic liquids. The final QSPR model derived by Genetic Function Approximation (GFA) contains

2 2
12 descriptors and quantified by the following statistical parameters: R train = 0.658, R test = 0.721 andAverage Absolute Relative Deviation (AARD) = 7.3%. The Applicability Domain (AD) of the model is alsoinvestigated. It turns out that the model’s domain is defined broadly enough to contain all the trainedand test sets which verified the reliability of the model. Finally, the proposed model has been scruti-nized by several validation techniques and its robustness and reliability is investigated. The results of thevalidation techniques indicate the present model is robust, stable and reliable one.
. Introduction

Ionic liquids (ILs) as a new generation of novel solvents withegligible vapor pressures [1] and low melting points [2], supersedeost conventional volatile solvents in diverse engineering applica-

ions [3] and embark on a luminous path of “Green” Industry.Ionic liquids are generally referred to salts melt at or near room

emperature. The other promising fact about ionic liquids is thatheir properties could be tuned by altering the combination of theironic constituents to achieved desired physical, chemical and bio-ogical properties. In the other word, the physical properties of ioniciquids depend strongly on the nature of anion and cation structure,

hich can be altered willfully. This sounds interesting; howevernding the proper combination of anions and cations to yield

avored property is a major challenge. Owing to the enormous num-er of possible ionic liquids, finding the right one with the desired

onic liquids with trial and error is impossible. Instead, predictionodels which can relate the desire property to the structures of

onic constituents of ILs seems perquisite for synthesis effort.

∗ Corresponding author. Tel.: +98 21 77 92 65 80; fax: +98 21 77 92 65 80.E-mail addresses: [email protected], [email protected] (F. Gharagheizi).

040-6031/$ – see front matter © 2012 Elsevier B.V. All rights reserved.ttp://dx.doi.org/10.1016/j.tca.2012.09.011

© 2012 Elsevier B.V. All rights reserved.

Since the ionic liquids are defined with regard to their meltingpoints (Tm), study of the effect of structural features on this prop-erty seems important. Besides, Tm is important to determine theliquidous range which is an important factor for employment ofionic liquids as a reaction media.

Since last decade, several models were proposed to predictmelting points of ILs. The previous models allocated with theiraccuracies in terms of R2 and Absolute average deviation (AAD)are presented in Table 1. The predictive models for melting pointsof ILs could be categorized in two main groups: QuantitativeStructure–Property Relationships (QSPRs) and group contributionmethods. The first group dealing with numerical values calleddescriptors which are solely based on the molecular structures.The descriptors treated as variables in this method to develop apredictive model. The majority of previous models are fall in thiscategory [4–15]. Bini et al. [12] work is labeled as the instance ofQSPR method; however their derived model is based on the directintroduction of the atomic structures of ionic liquids instead ofcalculated descriptors.

The other group of models applied group contribution (GC)approach for model development [16–19]. In this methodology, thecontributions of cation or anion functional group are considered topredict the desired physical property. Owing to higher number of

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18 N. Farahani et al. / Thermochimica Acta 549 (2012) 17– 34

Table 1Review of previous model for prediction of melting points of ILs.

Year Model Authors Ionic liquid type No. of ILs R2 ARD% Ref.

2002 QSPR Katritzky et al. Imidazolium bromides 104 0.751 12.9 [4]Benzimidazolium bromides 45 0.690 7.13 [4]

2002 QSPR Katritzky et al. Pyridinium bromides 126 0.713 Not reported [5]2003 QSPR Eike et al. Tetraalkyl-ammonium bromide 75 0.775 17.5 [6]

(n-Hydroxyalkyl)-trialkyl-ammoniumbromide

34 0.766 29.33 [6]

2005 QSPR Carrera et al. Pyridinium 126 0.822 Not reported [6]2005 QSPR Trohalaki 1-Substituted-4-amino-1,2,4-

triazolium bromides, nitrates, andnitrocyanamides

40 0.8 6 [8,9]

2006 QSPR Sun et al. Imidazolium tetrafluoroborates 16 0.905 5.06 [10]Imidazolium hexafluorophosphates 25 0.921 3.16 [10]

2007 QSPR Ignacio Lopez-Martin et al. Imidazolium 84 0.869 Not reported [11]2008 QSPRa Bini et al. Pyridinium bromides 126 0.872 19.37 [12]2008 QSPR Torrecilla et al. Imidazolium 97 0.99 Not reported [13]2009 QSPR Ren et al. Pyridinium bromides, imidazolium

bromides, benzimidazolium bromides,and 1-substituted4-amino-1,2,4-triazolium bromides

288 0.712 24.33 [14]

2010 QSPR Yan et al. Imidazolium bromides andimidazolium chlorides

94 0.89 2.5 [15]

2006 GC Yamamoto et al. Diverse 60 0.65 Not reported [16]2009 GC Huo et al. Imidazolium and benzimidazolium 190 0.898 5.86 [17]2011 GC Krossing et al. Diverse 520 0.537 9.3 [18]

in QSP

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the desired property of the compounds absent in model deriva-tion. In this study, K-means clustering is applied to select training

2012 GC Lazzús Diverse

a Instead of molecular descriptors direct structure treatment was applied to obta

ariables, the prediction of models based on the group contribu-ion methods accompanied with the higher accuracies. There arewo types of model for prediction of melting point based on GC.he first type of models deals directly with the melting point andelates the functional group to this parameter [16,17,19]. In thisategory the model could be linear or non-linear. The second typef GC used the thermodynamic definition of melting point [18]. Inhermodynamic, the melting point is defined as the temperature ofquilibrium between solid and liquid state. Since the change of theibbs free energy equals zero at the equilibrium; the melting pointefines as follows:

m = �H

�S(1)

n this approach, two correlations one for enthalpy and the otheror entropy should be derived to construct a model to predict melt-ng point. The main problem associated with the previous modelss that they are based on the limited number ionic liquids. In addi-ion, the majority of them fail to account both anion and cationontribution in their model except the work of Lazzús [19].

As mentioned before, the reliable model for the prediction ofelting points of ILs must be based on the comprehensive data set

f ionic liquids incorporating high diverse ionic structures to ensurets reliability of prediction for a broad range of ionic liquids. In thistudy, QSPR model based the most comprehensive number of ioniciquids as well as diverse number of anion and cation is developedo predict melting points of ILs.

. Methodology

.1. Data preparation

Extensive literature review is conducted to extract the exper-mental melting points of 705 diverse Ionic liquids through 131eferences. The references of the experimental data points arerovided as supplementary materials. The selected ionic liquids
re based on Sulfonium, Ammonium, Pyridinium, 1,3-Dialkylmidazolium, Tri-alkyl imidazolium, Phosphonium, Pyrrolidinium,ouble imidazolium, 1-Alkyl imidazolium, Piperidinium, Pyrro-
ine, Oxazolidinium, Amino acids, Guanidinium, Morpholinium,

400 0.884 7.07 [19]

R correlation.

Isoquinolinium and Tetra-alkyl imidazolium. As well as highdiversity of selected ionic liquids, the collected experimentaldata covering a wide range of melting points (197.65–542.65 K).There are 350 cations and 62 anions present in the structuresof studied ionic liquids. As far as authors concerned, this is themost comprehensive data set of cation and anion treated for themelting point model. The structure and abbreviation of the anionand cation are provided as supplementary materials

2.2. Calculation of descriptors

In order to optimize the 3D chemical structure of each cation andanion, the Dreiding Force field [20] as explained by Chemaxon’sJChem [21] was employed. Next, the final optimized structureswere exported to the sarchitect software [22] for the sake ofmolecular descriptors calculation. Sarchitect can compute 1084physicochemical descriptors – constitutional, 2D and 3D descrip-tors. After the completion of descriptors calculation, the descriptorswhich could not be calculated for some anions or cations werecompletely omitted. Then, the pair correlation is conducted overthe pool of anion and cation descriptors to omit highly correlateddescriptors. Any of two descriptors with the pair correlation above0.9 was eliminated from the descriptor pool. The numbers of finalapplied descriptors for the anion and cation part of ILs are 298 and628, respectively.

2.3. Training and test set selection [23]

Typically, to construct a reliable QSPR model the selected exper-imental data divided into the two parts: training and test sets.The first set of data applied to construct a QSPR model. Theother set is used to check the ability of the model to predict

and test sets. K-means clustering is a method of cluster anal-ysis which aims to partition n observations into K clusters inwhich each observation belongs to the cluster with the nearestmean.

ochimica Acta 549 (2012) 17– 34 19

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.4. Diversity test

To ensure the diversity of ionic liquids present in both train-ng and test sets the diversity test is conducted in this study. To

easure the diversity of ILs in term of numbers, the Euclideanistance approach is applied. Similar to its geometrical definition,uclidian distance measures the closeness of molecular structuresn n-dimensional descriptor space:

Each IL (Xi) is defined as a vector of corresponding molecularescriptors incorporating anion and cation descriptors (xim) as itslements where m is number of all calculated descriptors.

i = (xi1, xi2, xi3, ..., xim) (2)

distance score of two different compounds is defined as follows:

ij =∥∥Xi − Xj

∥∥ =

√√√√m∑

k=1

(xik − xjk)2 (3)

ext, the mean distance of one sample to the remaining ones isalculated as follows:

i =

n∑j=1

di,j

n − 1(4)

here n refers to number of all compounds. Then, the calculatedean distances are normalized according to following definition:

iNorm = di − dmin

dmax − dmin

(5)

iNorm Reveals the structural diversity of ionic liquid (i) in compar-

son of others. Fig. 1 presents the values of similarity test for bothest and train sets of studied ionic liquids. As it is shown in thisgure, the population of points is denser in vicinity of zero sinceearly one third of studied ionic liquids belong to the one group1,3-Dialkyl imidazolium). In addition, the scatter distribution ofhe points in this figure indicates the diverse array of both test andraining sets.

. Genetic function approximation (GFA)

GFA – as a genetic based variable selection approach –nvolves the combination of multivariate adaptive regressionplines (MARS) algorithm with genetic algorithm to evolve seriesf equations instead of one that best fit the training set data. Thepproach was originally proposed by the pioneering work of Rogersnd Hopfinger [24].

GFA approach works by generating of the initial population ofquations by random selection of descriptors. The goodness of each

Tm = intercept + TCationm + TAnion

m

intercept = 959.6153(±45.8285)

TCationm = 24.6002(± − 4.8970) Mor08pCatio

−244.665 (± − 24.8857)MATS1mCation − 6

−656.913 (± − 62.5673) X1ACation − 33.6686 (±

+0.1780 (±0.0146) t − veVSACation − 21.2957(±

TAnionm = −468.943 (± − 54.5890) X0AvAnion − 2

+0.2066 (± − 0.0866) AMWAnion + 0.0225 (± −

Fig. 1. Similarity test of the studied ionic liquids.

progeny equation is assessed by Friedman’s lack of fit (LOF) scorewhich is described by the following formula:

LOF(model) = 1N

LSE(model)(1 − (c+1+(d×p))

N

)2(6)

In this LOF function, c is the number of non-constant basis func-tions, N is the number of samples in the data set, d is a smoothingfactor to be set by the user, and p is the total number of parame-ters in the model and the LSE is the least square error of the model.Employment of LOF leads to the models with the better predic-tion without over-fitting.The superior models in terms of fitnesswere selected as the “parents” and new generation of equationswere evolved by the “cross-over” operation. In cross-over opera-tion, each parent is split randomly in two parts from crossing point,and the first substring of the first parent combined with the sec-ond substring of the second parent to create two new children. Thisprocess continues until no significant fitness improvement of themodel observed in the population. For a population of 300 models,3000–10,000 genetic operations are usually sufficient to achieveconvergence.

4. Result and discussion

The proposed QSPR model for the prediction of melting pointsof ILs based on the GFA contains 12 descriptors:

8.6747 (± − 8.8114) MATS4vCation

4.3378) IC2Cation

5.2520) ATS7eCation

.4326 (± − 0.4928) nXAnion

0.0028) tNPSAAnion

(7)

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R2 = 0.658; R2adj = 0.657;

nTraining = 563; nTest = 142;

F = 1079.63; SDEP = 28.98; RMSE = 26.85;

Q 2 = 0.655; Q 2boot = 0.654; Q 2

ext = 0.689

a = −0.016; Kx = 0, Kxy = 0.811;

�K = 0.811; �Q = 0; Rp = 0; RN = 1

n Eq. (7):

IC2 stands for information content index of neighborhood sym-metry of second order, for the cation part of ionic liquids. Theinformation content descriptor encourages complexity of themolecule, which roughly relates to increased asymmetry. Insimple terms, molecular complexity is a function of the size,symmetry, elemental molecular composition, molecular branch-ing, and centricity. Besides, this descriptor encodes informationabout molecule entropy. As we can see, the entropy appears inthe definition of the melting point temperature; so, our modelcan capture the true nature of melting point by including thisdescriptor.MATS4v and MATS1m Moran autocorrelation [25] of lag 4 andlag 1, respectively weighted by van der Waals volume and atomicmass. This descriptor is defined in order to reflect the contributionof a van der Waals volume as well as atomic mass of atmos in thestructure of cation to the melting point of ILs.Mor08p and Mor29u are 3D-Morse (Molecule Representation ofStructures based on Electron diffraction) [26] descriptor calledsignal 25/un weighted. Morse descriptors are derived by frominfra-red spectra simulation using a generalized scattering func-tion. These descriptors define as follows:

or(s, w) =n∑

i=2

i−1∑j=1

wiwj sin(s · rij)/(s · rij) (8)

here w and rij are weight and Euclidian distance between i,j atoms.orse descriptors also referred as a transformation of 3D struc-

ures, in which atomic 3D structures could be transformed into theolecular descriptors. It also reveals the relation of 3D structure of

he molecules with its physical, chemical and biological properties.

X1A stands for average connectivity index of order 1 [27]. Thisdescriptor belongs to Kier-Hall Connectivity Indices which iscalculated from the Hydrogen-depleted molecular graph.X1Adefines as:

1A =(

1b

)∑b

(ıi.ıj)−1/2 (9)

here b is the number of total bond, and for each bond ıi ıj ishe product of the vertex degrees of the end atoms i and j. Thisescriptor suggests that branching in the structure of cation wouldecrease the melting point. This behavior is consistent with theory,ince branching accounts for entropy amplification which result inelting point reduction.

t-veVSA stands for Van der Waals surface area of atoms withnegative charge. This descriptor reveals that introducing biggeratoms or molecules with negative partial charges to the structureof ionic liquid’s cation, would contribute positively to the melting
point.ATS7e is Broto-Moreau autocorrelation of a topological structure– lag 7/weighted by atomic Sanderson electronegativities [28]and defines as follows:
ica Acta 549 (2012) 17– 34

ATS7e =n∑

i=1

n∑j=1

ıij(ei.ej) (10)

where ei and ej are the Sanderson electronegativities of atomswith �ij topological distance of 7. �ij is Kronecker delta which equalsto zero for pairs of atoms with topological distances other than 7.

• X0Av is average valence connectivity index chi-0 [27] and definesas follows:

�0A = 1

n

n∑i=1

ı−1/2i

(11)

where n is the number of nodes in the Hydrogen-depleted graph,ıi is the vertex degree of the ith atom defined as the number ofnon-Hydrogen neighbors in the molecular graph. This descriptorcontributes negatively to the melting point.

• NX is the number of halogen atoms in anion structure of ionicliquid. The negative coefficient of this descriptor suggests thatanions with the higher number of halogen atoms have lowermelting points.

• AMW is average molecular weight of the anion and can be rep-resentative of the size anions. According to this descriptor, thebulkier the anion, the higher melting point.

• tNPSA stands for non-polar accessible surface area.

The related statistical parameters for obtained linear model arepresented below the Eq. (7).

where ntraining and ntest are the numbers of compounds avail-able in training set and test set, respectively, and R2 is the squaredcorrelation coefficients of the model. RMSE and SDE are the rootmean squared error of the model results in comparison with theexperimental values and standard deviation error, respectively.

4.1. Applicability domain [29–31]

Organization for Economic Cooperation and Development(OECD) proposed five principals for QSPR validation:

1. A defined endpoint;2. An unambiguous algorithm;3. A defined applicability domain;4. Appropriate measures of goodness-of-fit, robustness and predic-

tivity; and5. Mechanistic interpretation, if possible

Among aforementioned principals, Applicability Domain (AD)seems to be the most important one. Applicability domain is a theo-retical spatial domain defined by the molecular descriptors and themodeled responses and the nature of training sets. When a model isbuilt on the specific domain based on the compounds of the train-ing set, the prediction of the properties of absent compound wouldbe valid if it is “similar” to the training set molecules. In other word,prediction conducted within the domain based on interpolation isreliable. Otherwise, validity of the prediction outside of domainconducted by extrapolation is disputed. The lack of general andaccepted definition of similarity, make researchers to define AD totest the reliability of the QSPR models. In this study, Williams graphis used to depict AD and presented as Fig. 2. In this approach, lever-
age or hat indices are calculated based on Hat matrix (H) with thefollowing definition:
H = X(XT X)−1

XT (12)

N. Farahani et al. / Thermochimi

w(Ts

s(iatd

EdilT

4

tt(afpmyt

s(

F

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Fig. 2. Applicability domain of the proposed model.

here X is a two-dimensional matrix comprising n ionic liquidsrows) and k descriptors belong to both anion and cation (columns).he leverages or hat values (hi) of the chemicals in the descriptorpace are the diagonal elements of H.

Williams graph shows the correlation of hat values andtandardized cross-validated residuals (R). A warning leverageh* = 0.011) – blue vertical line – is generally fixed at 3n/p, where ns number of training chemicals and p the number of model vari-bles plus one. The leverage of 3 is considered as a cut-off valueo accept the points that lay ±3 (two horizontal red lines) standardeviations from the mean (to cover 99% normally distributed data).

The AD is located in the region of 0 ≤ h ≤ 0.011 and −3 ≤ R ≤ 3.xistence of the majority of training and test data points in thisomain reveals that both model derivation and prediction are done

n applicability domain which results in a valid model.“Good higheverage” points are located in domain of h > 0.011 and −3 ≤ R ≤ 3.hese points fit the model well, and make it more stable and precise.

.2. Validation

To be usefully applicable, a QSPR model must be capture the truerend of the desired property from training set reproduce them forhe test set (goodness of fit, verified by R2), be stable and robustverified by internal cross-validations: leave-one-out, bootstrap)nd, most importantly, by extracting the maximum informationrom the limited existing knowledge, it must be able to reliablyredict data for new chemicals not involved in model develop-ent (external validation). In addition, F-Test and RQK test and

-scrambling also applied to assure the reliability and stability ofhe model.

F is the F-ratio which is defined as the ratio between the modelummation of squares (MSS) and the residual summation of squaresRSS) [32,33]:

= MSS/dfMRSS/dfE

(13)

here dfM and dfE denote the degree of freedom of the obtainedodel and the overall error respectively. It is a comparison between

he model explained variance and the residual variance. The
btained F value in this study is 1079.63. The high values of the-ratio test indicate the reliability of models.
Leave-one-out cross validation technique [34] was applied andhe value of Q2

Loo is 0.655. To evaluate this statitistical parameter,

ca Acta 549 (2012) 17– 34 21

the train set as well as model’s descriptors are considered. If theabsolute difference of this value and calculated R2 is small, thereliability of the model would be validated [35–37].

Adjusted-R squared is another validation technique used in thisstudy [33] and its calculated value is 0.6574. The less differencebetween this value and the R2 parameter, the more validity of themodel would be expected [38,39].

To ensure the reliability of the model prediction, Todeschiniet al. [33,40] Proposed 4 RQK constraints which must be completelysatisfied:

1. �K = KXY − KX > 0 (Quick rule)2. �Q = Q2

LOO − Q2ASYM > 0 (Asymptotic Q2 rule)

3. RP > 0 (Redundancy RP rule)4. RP > 0 (Over-fitting RN rule)

The calculated values of RQK test are presented as follows:�K = 0.811, �Q = 0, RP = 0 and RN = 1. Positive or zero correspon-dent values of these parameters indicates not only the validity ofthe model, but also approval for non-chance correlation.

Bootstrap is another validation technique applied in this study[41]. “Q2

boot′′ is the key parameter of Bootstrap and defines as theaverage of the Prediction Error of Sum of Squares (PRESS) calculatedin this technique. PRESS is defined as follows:

PRESS =n∑

i=1

(yi − yi/i) (14)

where yi/i denotes the response of the ith predicted melting pointusing the obtained model ignoring the use of ith melting point.The bootstrapping has been repeated 5000 times. Consequently, thevalue Q2

boot parameter of the obtained model has been evaluatedto be 0.654. The less difference between Q2

boot and R2, the morereliable model [36,42,43].

In addition, y-scrambling validation technique was applied, totest the model for chance correlations [44]. The obtained value of“a” from this technique, interprets the possibility of the chancecorrelation: If the “a” value closes to zero, lack of chance corre-lations is verified. In other hand, by achieving large values of a, themodel would be considered as a chance correlation model. In thisstudy, the evaluated “a” value is −0.016. The y-scrambling shouldbe repeated hundreds of times (in this work 300 times). High valuesof parameter “a” indicate the instability of the model [39,43].

Finally, the external validation technique was applied [45]. Theobtained Q2

ext value is 0.689 is calculated. The less differencebetween this value and the R2 parameter, the more validity of themodel would be expected [35–39,42,43].

Fig. 3 depicts the deviation between predicted values of meltingpoints and the experimental ones.

In this study, AARD defines as follows:

AARD% = 100N

N∑i=1

∣∣∣∣Texp

m − Tcalcm

Texpm

∣∣∣∣i

(15)

The results obtained by the model suggests the model can accu-rately predict the melting points of both training and test sets:AARD of 7.35% for the 563 ILs used in the correlation set and AARDof 7% for the other 142 ILs used in the test set. For all substances (705ILs) the AARD is approximately 7%, and for 498 ILs of this databasethe deviations are below 10%. Refering to Table 1, the present studyinclude the largest number of investigated ionic liquids as well as
the wide variety of anions and cations. Table 2 presents studiedionic liquids and ARD values of model prediction.
The majorities of previous studies divided their data sets intosmaller ones and propose models for each split data sets. Since the


Table 2The abbreviation of ionic liquids and the ARD values of predicted melting point of studied ionic liquid.

ID Name Refs. Tpredm (K) ARD% Status

1 N,N-diethyl-N-methyl-N-(n-butyl)ammonium trifluoromethyltrifluoroborate [1] 299.16 10.7 Test2 1-Ethyl-2-methylpyrrolinium bis((trifluoromethyl)sulfonyl)imide [2] 343.43 7.9 Training3 1-Propyl-2-methylpyrrolinium iodine [2] 369.59 3.2 Training4 1-Propyl-2-methylpyrrolinium bis((trifluoromethyl)sulfonyl)imide [2] 316.06 8.2 Training5 1-Butyl-2-methylpyrrolinium iodine [2] 370.09 3.7 Training6 1-Butyl-2-methylpyrrolinium bis((trifluoromethyl)sulfonyl)imide [2] 316.56 2.4 Test7 N-butyl pyridinium bromide [3] 344.03 9.0 Training8 N-butyl pyridinium tetrafluoroborate [4] 305.29 5.8 Training9 N-butyl pyridinium bis((trifluoromethyl) sulfonyl)imide [5] 304.05 1.7 Training10 N-butyl pyridinium 2,2,3,3,4,4,5,5-octafluoropentyl sulfate [6] 293.84 6.4 Training11 N-butyl pyridinium benzoate [7] 297.21 4.7 Test12 N-hexyl pyridinium bis((trifluoromethyl) sulfonyl)imide [3] 305.27 11.8 Training13 N-dodecyl pyridinium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [8] 372.19 10.4 Test14 N-dodecyl pyridinium hexafluorophosphate [9] 352.21 7.1 Training15 N-tetradecyl pyridinium hexafluorophosphate [9] 356.75 10.2 Training16 N-hexadecyl pyridinium hexafluorophosphate [9] 367.93 7.8 Training17 N-octadecyl pyridinium hexafluorophosphate [9] 373.05 6.5 Training18 4-Methyl-N-butyl pyridinium benzoate [7] 313.23 10.4 Training19 1-Dodecyl-3-methylpyridinium hexafluorophosphate [9] 355.65 8.4 Training20 1-Methylimidazolium chloride [10] 342.44 0.8 Test21 1-Dodecyl-4-methylpyridinium hexafluorophosphate [9] 360.14 9.4 Training22 1-Methylimidazolium bromide [10] 351.24 11.8 Training23 1-Tetradecyl-3-methylpyridinium hexafluorophosphate [9] 362.37 6.2 Training24 1-Tetradecyl-4-methylpyridinium hexafluorophosphate [9] 367.21 6.7 Training25 1-Hexadecyl-3-methylpyridinium hexafluorophosphate [9] 369.56 6.5 Training26 1-Hexadecyl-4-methylpyridinium hexafluorophosphate [9] 374.53 7.6 Training27 1-Octadecyl-3-methylpyridinium hexafluorophosphate [9] 374.79 4.1 Test28 1-Octadecyl-4-methylpyridinium hexafluorophosphate [9] 379.97 5.2 Training29 N-butyronitrile pyridinium chloride [9] 343.18 8.3 Test30 N-butyronitrile pyridinium tetrafluoroborate [11] 313.23 6.5 Training31 N-butyronitrile pyridinium hexafluorophosphate [12] 338.32 8.1 Test32 1-Methylimidazolium tetrafluoroborate [13] 312.50 4.0 Training33 N-SF5CF2CF2CH2CH2-pyridinium bis((trifluoromethyl)sulfonyl)imide [14] 273.22 10.8 Training34 SF5CF2CF2CH2CH2CH2CH2-pyridinium bis((trifluoromethyl)sulfonyl)imide [14] 264.47 9.2 Training35 SF5CF2CF2CF2CF2CH2CH2-pyridinium bis((trifluoromethyl)sulfonyl)imide [14] 281.11 9.1 Test36 N-fluoro-propyl-4,40-bipyridinium bis((trifluoromethyl)sulfonyl)imide [15] 338.11 0.9 Test37 N-fluoro-propyl-4,40-bipyridinium trifluoromethanesulfonate [15] 346.57 4.0 Training38 N-trifluoro-propyl-4,40-bipyridinium bis((trifluoromethyl)sulfonyl)imide [15] 359.90 0.3 Training39 N-trifluoro-propyl-4,40-bipyridinium trifluoromethanesulfonate [15] 368.36 0.8 Test40 1-Methylimidazolium bis((trifluoromethyl)sulfonyl)imide [10] 311.25 10.3 Training41 N-tridecylfluoro-octyl-4,40-bipyridinium bis((trifluoromethyl)sulfonyl)imide [15] 367.12 12.9 Training42 N-tridecylfluoro-octyl-4,40-bipyridinium trifluoromethanesulfonate [15] 375.58 0.4 Training43 N-heptadecylfluoro-decyl-4,40-bipyridinium bis((trifluoromethyl)sulfonyl)imide [15] 374.59 2.0 Training44 N-heptadecylfluoro-decyl-4,40-bipyridinium trifluoromethanesulfonate [15] 383.05 0.2 Training45 1-Methylimidazolium bis((perfluoroethane) [10] 297.14 4.6 Test46 N,N0-di(fluoro-propyl)-4,40-bipyridinium di[bis((trifluoromethane)sulfonyl)imide] [15] 316.40 6.2 Training47 N,N0-di(fluoro-propyl)-4,40-bipyridinium di[trifluoromethanesulfonate] [15] 324.86 10.3 Test48 N,N0-di(trifluoro-propyl)-4,40-bipyridinium di[bis((trifluoromethane)sulfonyl)imide] [15] 342.18 7.3 Training49 N,N0-di(trifluoro-propyl)-4,40-bipyridinium di[trifluoromethanesulfonate] [15] 350.64 6.8 Test50 N,N0-di(tridecylfluoro-propyl)-4,40-bipyridinium di[bis((trifluoromethane)sulfonyl)imide] [15] 379.94 10.0 Test51 N,N0-di(tridecylfluoro-propyl)-4,40-bipyridinium di[trifluoromethanesulfonate] [15] 388.40 11.4 Training52 di(N-fluoro-propyl bipyridinium)-butylene tetra[bis((trifluoromethane)sulfonyl)imide] [15] 377.92 4.1 Training53 di(N-trifluoro-propyl bipyridinium)-butylene tetra[bis((trifluoromethane)sulfonyl)imide] [15] 405.04 1.7 Training54 1-Methylimidazolium nitrate [10] 321.68 6.3 Training55 1-Butyl-3,5-dimethylpyridinium bromide [3] 364.34 1.0 Training56 1-Methylimidazolium trifluoromethanesulfonate [10] 319.71 10.5 Training57 1-Butyl-nicotinic acid butyl ester bis((trifluoromethyl)sulfonyl)imide [3] 293.17 1.8 Training58 1-Hexyl-3,5-dimethylpyridinium bis((trifluoromethyl)sulfonyl)imide [3] 323.78 14.4 Training59 1-Methylimidazolium hexafluorophosphate [10] 337.59 13.3 Training60 1-Hexyl-3-methyl-4-(dimethylamino)pyridinium bromide [3] 342.44 4.1 Test61 1-Hexyl-3-methyl-4-(dimethylamino)pyridinium bis((trifluoromethyl)sulfonyl)imide [3] 302.46 11.6 Training62 1-Hexyl-4-(4-methylpiperidino) pyridinium bis((trifluoromethyl)sulfonyl)imide [3] 314.02 1.3 Training63 N,N0-bis[3-(1-nonyloxymethyl)pyridinium chloride]methylenediamine [16] 336.43 1.4 Training64 N,N0-bis[3-(1-decyloxymethyl)pyridinium chloride]methylenediamine [16] 340.94 0.6 Training65 N,N0-bis[3-(1-undecyloxymethyl)pyridinium chloride]methylenediamine [16] 345.81 0.8 Test66 N,N0-bis[3-(1-dodecyloxymethyl)pyridinium chloride]methylenediamine [16] 349.53 2.2 Training67 1-Methylimidazolium trifluoroacetate [17] 312.92 3.5 Training68 1-Methylimidazolium acetate [17] 253.77 1.4 Training69 N-dodecyl-isoquinolinium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [8] 371.95 7.8 Training70 1-Ethylimidazolium chloride [10] 341.28 3.1 Training71 1-Ethylimidazolium bromide [10] 350.07 5.1 Test72 1-Ethylimidazolium perchlorate [10] 326.57 11.0 Training73 1-Ethylimidazolium nitrate [10] 320.52 5.4 Training74 1-Ethylimidazolium trifluoromethanesulfonate [10] 318.55 13.3 Training75 (R)-3-butyl-4-ethyl-2-isopropyl-2-thiazoliniumiodine [18] 366.17 10.7 Training76 (R)-3-butyl-4-ethyl-2-isopropyl-2-thiazolinium hexafluorophosphate [18] 338.97 17.2 Training

N. Farahani et al. / Thermochimica Acta 549 (2012) 17– 34 23

Table 2 (Continued)


77 (R)-3-dodecyl-4-ethyl-2-isopropyl-2-thiazolinium hexafluorophosphate [18] 355.07 12.7 Training78 Tri-methylsulfonium bis((trifluoromethyl) sulfonyl)imide [19] 269.12 15.3 Training79 Tri-methylsulfonium dicyanoamide [20] 258.44 5.0 Training80 Tri-methylsulfonium 2,2,2-trifluoro-N-(trifluoromethylsulfonyl)acetamide [21] 265.63 13.0 Training81 Tri-ethylsulfonium bis((trifluoromethyl)sulfonyl)imide [22] 296.99 14.6 Training82 Tri-ethylsulfonium 2,2,2-trifluoro-N-(trifluoromethylsulfonyl)acetamide [21] 293.51 3.8 Training83 Tri-butylsulfonium bis((trifluoromethyl) sulfonyl)imide [19] 277.64 4.5 Test84 Ethyldimethylsulfonium dicyanoamide [20] 243.90 0.5 Test85 Ethyldipropylsulfonium dicyanoamide [20] 252.23 5.5 Training86 Tetramethylammonium bis((trifluoromethyl) sulfonyl)imide [21] 388.34 3.7 Training87 Trimethylethylammonium bis((trifluoromethyl) sulfonyl)imide [21] 354.03 6.4 Training88 Trimethylpropylammonium bis((trifluoromethyl)sulfonyl)imide [23] 330.33 11.9 Training89 Trimethylpropylammonium

N-(trifluoromethylsulfonyl)pentafluoroethylsulfonamide[22] 324.84 11.2 Test

90 Trimethylpropylammonium2,2,2-trifluoro-N-(trifluoromethylsulfonyl)acetamide

[21] 326.85 15.4 Training

91 Trimethyl-isopropylammonium bis((trifluoromethyl)sulfonyl)imide [21] 379.55 5.6 Test92 Dimethyl-diethylammonium bis((trifluoromethyl)sulfonyl)imide [24] 347.18 6.0 Training93 Trimethyl-allylammonium bis((trifluoromethyl) sulfonyl)imide [21] 348.39 10.9 Training94 Trimethyl-propargylammonium bis((trifluoromethyl)sulfonyl)imide [21] 348.98 9.7 Training95 N,N,N-trimetyl-N-butanesulfonic acid ammonium hydrogen sulfate [25] 250.55 4.4 Training96 N,N,N0,N0-tetramethyl-N,N0-dihexyl ethylenediammonium

di[bis(trifluoromethanesulfonyl) amide][26] 311.89 12.7 Training

97 N,N,N0,N0-tetramethyl-N,N0-dioctyl ethylenediammoniumdi[bis(trifluoromethanesulfonyl) amide]

[26] 320.20 9.3 Test

98 Methoxymethylenedimethylethylammonium tetrafluoroborate [27] 290.19 12.8 Training99 Methoxymethylenedimethylethylammonium bis(oxalato)borate [28] 284.02 12.3 Test100 N,N,N0,N0-tetramethyl-N,N0-dibutyl-1,3-propanediammonium

di[bis(trifluoromethanesulfonyl)amide][26] 315.24 5.7 Training

101 N,N,N0,N0-tetramethyl-N,N0-diamyl-1,3-propanediammoniumdi[bis(trifluoromethanesulfonyl)amide]

[26] 299.05 7.7 Test

102 N,N,N0,N0-tetramethyl-N,N0-dihexyl-1,3-propanediammoniumdi[bis(trifluoromethanesulfonyl) amide]

[26] 300.57 10.8 Training

103 N,N,N0,N0-tetramethyl-N,N0-diheptyl-1,3-propanediammoniumdi[bis(trifluoromethanesulfonyl)amide]

[26] 296.63 7.3 Training

104 N,N,N0,N0-tetramethyl-N,N0-dioctyl-1,3-propanediammoniumdi[bis(trifluoromethanesulfonyl) amide]

[26] 298.87 6.6 Training

105 N,N,N0,N0-tetramethyl-N,N0-diethyl-1,6-hexanediammoniumdi[bis(trifluoromethanesulfonyl) amide]

[26] 315.67 0.8 Test

106 N,N,N0,N0-tetramethyl-N,N0-dibutyl-1,6-hexanediammoniumdi[bis(trifluoromethanesulfonyl)amide]

[26] 311.07 13.4 Training

107 N,N,N0,N0-tetramethyl-N,N0-dihexyl-1,6-hexanediammoniumdi[bis(trifluoromethanesulfonyl)amide]

[26] 307.05 5.3 Training

108 Dimethyl-ethyl-propylammonium bis((trifluoromethyl)sulfonyl)imide [24] 305.01 3.3 Training109 Propylammonium nitrate [29] 309.51 11.7 Training110 Propylamine trifluoroacetate [30] 300.74 11.5 Test111 Propylammonium formate [31] 286.28 11.4 Test112 Butylammonium formate [32] 297.98 8.3 Test113 Pentylammonium formate [31] 286.40 0.4 Training114 2-Methylpropylammonium formate [32] 332.46 11.1 Training115 3-Methylbutylammonium formate [32] 321.14 0.3 Training116 Trimethyl-butylammonium bis((trifluoromethyl) sulfonyl)imide [24] 311.71 11.3 Training117 3-Trimethylammoniopropanesulfonic acid hydrosulfate [33] 248.43 4.9 Training118 3-Triethylammoniopropanesulfonic acid hydrosulfate [33] 258.83 2.0 Training119 3-tri-n-Butylammoniopropanesulfonic acid hydrosulfate [33] 256.63 3.6 Training120 N-benzyl-N,N,N-triethylammonium dicyanoamide [34] 355.08 0.4 Training121 N-benzyl-N,N,N-triethylammonium trifluoromethanesulfonate [34] 374.22 2.2 Training122 N-phenyl-N,N,N-trimethylammonium thiocyanate [34] 393.59 1.1 Training123 N-phenyl-N,N,N-trimethylammonium Saccharinate [34] 401.17 14.0 Training124 N-phenyl-N,N,N-trimethylammonium dicyanoamide [34] 384.08 1.6 Training125 N-phenyl-N,N,N-trimethylammonium trifluoromethanesulfonate [34] 403.22 13.2 Training126 N-phenyl-N,N,N-trimethylammonium Tosylate [34] 387.60 8.3 Training127 Triethyldodecylammonium bis ((trifluoromethyl)sulfonyl)imide [35] 312.91 11.7 Training128 Triethyl(methoxymethyl)ammonium bis ((trifluoromethyl)sulfonyl)imide [35] 305.26 13.0 Test129 Triethyl-methylammonium bis((trifluoromethyl) sulfonyl)imide [21] 347.91 13.5 Training130 Triethyl-methylammonium

2,2,2-trifluoro-N-(trifluoromethylsulfonyl)acetamide[21] 344.43 17.5 Training

131 Dibenzyldimethylammonium bromide [36] 465.98 4.0 Training132 Dibenzyldimethylammonium tetrafluoroborate [37] 427.25 2.7 Training133 Dibenzyldimethylammonium hexafluorophosphate [37] 452.33 7.9 Test134 Dimethyldi(3-methylbenzyl)ammonium chloride [37] 449.43 6.4 Training135 Dimethyldi(3-methylbenzyl)ammonium tetrafluoroborate [37] 419.49 3.8 Test136 Dimethyldi(3-methylbenzyl)ammonium hexafluorophosphate [37] 444.57 2.4 Training137 Dimethyldi(4-methylbenzyl)ammonium bromide [37] 477.52 0.5 Test138 Dimethyldi(4-methylbenzyl)ammonium tetrafluoroborate [37] 438.79 8.3 Training139 Dimethyldi(4-methylbenzyl)ammonium hexafluorophosphate [37] 463.87 5.5 Test140 Ethoxymethylene-dimethyl-ethylammonium bis(oxalato)borate [28] 287.13 10.2 Training


Table 2 (Continued)


141 Methoxyethyl-dimethyl-ethylammonium bis(oxalato)borate [28] 290.19 9.7 Training142 Tetraethylammonium tetrafluoroborate [38] 363.05 5.2 Training143 Tetraethylammonium bis((trifluoromethyl) sulfonyl)imide [38] 361.80 4.1 Training144 Tetraethylammonium

N-(trifluoromethylsulfonyl)pentafluoroethylsulfonamide[22] 356.31 4.1 Training

145 Tetraethylammonium bis((perfluoroethane) sulfonyl)imide [38] 347.69 2.4 Training146 Tetraethylammonium tris(trifluoromethylsulfonyl)methide [38] 357.21 11.9 Training147 Dimethyl-ethyl-butylammonium bis((trifluoromethyl)sulfonyl)imide [24] 303.20 14.4 Training148 Dimethyl-propyl-butylammonium bis((trifluoromethyl)sulfonyl)imide [24] 298.16 3.5 Training149 Dimethyl-propyl-butylammonium tricyanomethanide [12] 279.55 0.0 Test150 Trimethyl-hexylammonium tetrafluoroborate [27] 307.51 10.0 Training151 Trimethyl-hexylammonium bis ((trifluoromethyl)sulfonyl)imide [21] 306.26 2.0 Training152 Methyl-ethyl-di(i-propyl)ammonium bis((trifluoromethyl)sulfonyl)imide [39] 366.64 11.3 Training153 Diethyl-di(iso)propylammonium bis((trifluoromethyl)sulfonyl)imide [39] 375.61 10.8 Training154 Trimethyl-octylammonium bis((trifluoromethyl) sulfonyl)imide [21] 309.23 11.2 Training155 Triethyl-(2-methylbutyl)-ammonium bromide [40] 366.03 1.9 Test156 Tetrapropylammonium Saccharinate [41] 306.68 16.9 Training157 Triethyl-hexylammonium bis((trifluoromethyl) sulfonyl)imide [24] 304.19 3.8 Training158 Tetrabutylammonium bis((trifluoromethyl) sulfonyl)imide [38] 304.59 16.1 Test159 Tetrabutylammonium 2,2,3,3,4,4,5,5-octafluoropentyl sulfate [6] 294.39 11.0 Training160 Tetrabutylammonium tris Tetrabutylammonium tris [38] 300.00 9.7 Training161 Tributyl-hexylammonium bis((trifluoromethyl) sulfonyl)imide [42] 300.45 0.4 Training162 Tributyl-hexylammonium Tosylate [43] 293.29 9.2 Training163 Tetrapentylammonium bis((trifluoromethyl) sulfonyl)imide [44] 288.74 3.2 Training164 Tetrapentylammonium


165 Tetrapentylammonium 2,2,2-trifluoro-N-(trifluoromethylsulfonyl)acetamide [22] 285.26 1.3 Training166 Tetrahexylammonium bis((trifluoromethyl) sulfonyl)imide [44] 303.58 14.0 Training167 Trioctyl-propylammonium bromide [40] 349.12 0.6 Training168 Tetraheptylammonium bis((trifluoromethyl) sulfonyl)imide [44] 309.50 8.8 Training169 Tripentyl-tetradecylammonium bromide [40] 350.93 4.4 Training170 Tetraoctylammonium bis((trifluoromethyl) sulfonyl)imide [44] 314.86 3.5 Training171 Tridodecyl-methylammonium bromide [40] 355.22 2.0 Training172 Tetradecylammonium bis((trifluoromethyl) sulfonyl)imide [44] 338.20 11.3 Test173 Isopropyldimethyl[(1R,2S,5R)-()-menthoxymethyl]ammonium

bis((trifluoromethyl) sulfonyl)imide[45] 314.16 0.3 Training

174 Butyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium iodine [45] 363.10 2.5 Training175 Butyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium perchlorate [45] 326.05 6.9 Training176 Butyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium tetrafluoroborate [45] 310.82 9.0 Test177 Butyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium

hexafluorophosphate[45] 335.90 10.7 Training

178 Butyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium trifluoroacetate [45] 311.23 9.8 Training179 Hexyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium tetrafluoroborate [45] 303.47 3.7 Training180 Heptyldimethyl[(1R,2S,5R)-()-menthoxymethyl]ammonium tetrafluoroborate [45] 302.49 11.6 Training181 Octyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium tetrafluoroborate [45] 308.69 14.4 Training182 Nonyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium tetrafluoroborate [45] 307.83 10.0 Test183 Decyldimethyl[(1R,2S,5R)-()-menthoxymethyl] ammonium tetrafluoroborate [45] 307.61 6.3 Training184 Undecyldimethyl[(1R,2S,5R)-()-menthoxymethyl]ammonium chloride [45] 338.63 7.1 Training185 Dodecyldimethyl[(1R,2S,5R)-()-menthoxymethyl]ammonium

bis((trifluoromethyl) sulfonyl)imide[45] 314.51 0.4 Test

186 Benzyldimethyl[(1R,2S,5R)-()-menthoxymethyl]ammonium tetrafluoroborate [45] 353.19 4.7 Training187 Benzyldimethyl[(1R,2S,5R)-()-menthoxymethyl]ammonium

bis((trifluoromethyl) sulfonyl)imide[45] 351.94 10.3 Training

188 Cr(CO)3(h6-C6H5CH2NMe2 (CH2)2OH) bis(trifluoromethylsulfonyl)imide [46] 337.61 6.1 Training189 N,N-diethyl-N-methyl-N-(n-propyl)ammonium

pentafluoroethyltrifluoroborate[1] 297.04 9.2 Training

190 N,N-diethyl-N-methyl-N-(n-propyl)ammonium(heptafluoro-n-propyl)trifluoroborate

[1] 292.18 11.5 Training

191 N,N-diethyl-N-methyl-N-(n-propyl)ammonium(nonafluoro-n-butyl)trifluoroborate

[1] 287.33 12.2 Test

192 N,N-diethyl-N-methyl-N-(n-propyl)ammoniumbis((trifluoromethyl)sulfonyl)imide

[1] 305.70 6.5 Training

193 N,N-diethyl-N-methyl-N-(n-butyl)ammonium pentafluoroethyltrifluoroborate [1] 294.27 2.1 Test194 N,N-diethyl-N-methyl-N-(n-butyl)ammonium

(heptafluoro-n-propyl)trifluoroborate[1] 289.40 10.4 Training

195 N,N-diethyl-N-methyl-N-(n-butyl)ammonium(nonafluoro-n-butyl)trifluoroborate

[1] 284.56 14.6 Training

196 N,N-diethyl-N-methyl-N-(n-butyl)ammoniumbis((trifluoromethyl)sulfonyl)imide

[1] 302.92 7.4 Training

197 N,N,N-trimethyl-N-(2-methoxyethyl)ammonium tetrafluoroborate [1] 312.58 4.5 Training198 N,N,N-trimethyl-N-(2-methoxyethyl) ammonium

trifluoromethyltrifluoroborate[1] 307.58 12.2 Training

199 N,N,N-trimethyl-N-(2-methoxyethyl) ammoniumpentafluoroethyltrifluoroborate

[1] 302.68 0.2 Training

200 N,N,N-trimethyl-N-(2-methoxyethyl) ammonium(heptafluoro-n-propyl)trifluoroborate

[1] 297.82 0.6 Training


Table 2 (Continued)


201 N,N,N-trimethyl-N-(2-methoxyethyl) ammonium(nonafluoro-n-butyl)trifluoroborate

[1] 292.97 9.3 Training

202 N,N,N-trimethyl-N-(2-methoxyethyl)ammoniumbis((trifluoromethyl)sulfonyl)imide

[1] 311.34 0.4 Training

203 N,N-methyl-N-ethyl-N-(2-methoxyethyl) ammonium tetrafluoroborate [1] 296.36 6.9 Training204 N,N-methyl-N-ethyl-N-(2-methoxyethyl) ammonium


205 N,N-methyl-N-ethyl-N-(2-methoxyethyl) ammonium(nonafluoro-n-butyl)trifluoroborate

[1] 276.75 12.9 Training

206 N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate [47] 298.36 5.7 Training207 N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium


208 N,N,N-triethyl-N-(2-methoxyethyl)ammonium tetrafluoroborate [1] 309.48 6.0 Test209 N,N,N-triethyl-N-(2-methoxyethyl)ammonium trifluoromethyltrifluoroborate [1] 304.48 7.5 Training210 N,N,N-triethyl-N-(2-methoxyethyl)ammonium

pentafluoroethyltrifluoroborate[1] 299.58 8.5 Training

211 N,N,N-triethyl-N-(2-methoxyethyl)ammonium(heptafluoro-n-propyl)trifluoroborate

[1] 294.72 5.6 Test

212 N,N,N-triethyl-N-(2-methoxyethyl)ammonium(nonafluoro-n-butyl)trifluoroborate

[1] 289.87 2.0 Training

213 N,N,N-triethyl-N-(2-methoxyethyl)ammoniumbis((trifluoromethyl)sulfonyl)imide

[1] 308.24 5.1 Training

214 N,N,N-trioctyl-N-methylammonium tetrafluoroborate [48] 306.87 7.9 Training215 N,N,N-trioctyl-N-methylammonium tetrakis

(3,5-bis(trifluoromethyl)phenyl)borate[8] 351.93 13.8 Training

216 N,N,N-trioctyl-N-methylammonium nitrate [48] 316.05 13.2 Training217 N,N,N-trioctyl-N-methylammonium 2,2,3,3,4,4,5,5-octafluoropentyl sulfate [6] 295.41 8.9 Training218 N,N,N-trioctyl-N-methylammonium Tosylate [34] 298.45 15.0 Training219 N,N,N-trioctyl-N-methylammonium hexafluorophosphate [48] 331.95 2.4 Training220 N,N,N-trioctyl-N-methylammonium acetate [48] 248.13 1.2 Training221 N,N,N-trioctyl-N-methylammonium formate [48] 292.82 6.8 Training222 1-Octyl-4-aza-1-azonia-bicyclo[2.2.2]octane

bis((trifluoromethyl)sulfonyl)imide[49] 324.70 8.5 Training

223 N,N,N0,N0-tetramethylmethanediaminedi[4,4,4-trifluoro-1-(2-furyl)-1,3-butanedionate]

[50] 358.69 1.0 Training

224 N,N,N0,N0-tetramethylethanediaminedi[1,1,1,5,5,5-hexafluoro-2,4-pentanedionate]

[50] 343.69 3.5 Test

225 N,N,N0,N0-tetramethylethanediamine di[2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionate]

[50] 331.60 5.9 Training

226 N,N,N0,N0-tetramethyl-1, 3-propanediaminedi[2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionate]

[50] 314.20 1.0 Training

227 N,N,N0,N0-tetramethyl-1,6-hexanediaminedi[1,1,1,5,5,5-hexafluoro-2,4-pentanedionate]

[50] 318.49 16.9 Training

228 N,N,N0,N0-tetramethyl-1,6-hexanediaminedi[4,4,4-trifluoro-1-(2-furyl)-1,3-butanedionate]

[50] 327.40 13.4 Training

229 1,4,7,10-Tetraazacyclododecane di[1,1,1-trifluoro-2,4-pentanedionate] [50] 367.23 13.4 Training230 1,4,7,10-Tetraazacyclododecane di[1,1,1,5,5,5-hexafluoro-2,4-pentanedionate] [50] 382.10 2.6 Test231 1,4,7,10-Tetraazacyclododecane

di[2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionate][50] 370.01 14.0 Training

232 1,4,7,10-Tetraazacyclododecanedi[4,4,4-trifluoro-1-(2-furyl)-1,3-butanedionate]

[50] 391.00 3.5 Training

233 Tri-n-propylammonium 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate [51] 285.32 8.4 Training234 Tributylammonium nitrate [29] 308.12 4.6 Training235 Tri-i-octylammonium 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate [51] 300.35 14.6 Training236 Dipropylammonium thiocyanate [29] 295.68 6.1 Training237 Di-i-propylammonium

2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionate[52] 352.74 3.1 Training

238 Di-n-butylammonium 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate [52] 296.52 17.0 Training239 Di-i-butylammonium

2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionate[52] 312.41 7.1 Training

240 1-Ethyl-4-aza-1-azonia-bicyclo[2.2.2]octanebis((trifluoromethyl)sulfonyl)imide

[53] 385.55 10.4 Test

241 Ethylammonium bis((trifluoromethyl)sulfonyl) imide [22] 264.70 17.6 Training242 Ethylammonium nitrate [32] 275.13 2.5 Training243 Ethylammonium hydrosulfate [32] 264.70 15.5 Training244 Ethylammonium formate [31] 251.90 2.4 Training245 Ethylammonium DL-lactate [32] 223.71 3.5 Training246 2-Hydroxyethylammonium nitrate [31] 304.18 6.2 Test247 Dimethyldipentylammonium bromide [54] 339.97 2.7 Training248 Dimethyldipentylammonium iodine [54] 353.51 1.7 Training249 Dihexyldimethylammonium bromide [54] 338.41 3.5 Training250 Dihexyldimethylammonium iodine [54] 351.96 10.6 Training251 Diethyldipentylammonium bromide [54] 338.29 2.3 Training252 Diethyldipentylammonium iodine [54] 351.84 4.4 Test253 Diethyldihexylammonium bromide [54] 336.86 3.1 Training254 Diethyldihexylammonium iodine [54] 350.41 1.3 Training255 [Me3N(CH2)2OC(O)(CH2)2CH3] Saccharinate [41] 315.14 13.0 Training


Table 2 (Continued)


256 [Me3N(CH2)2OC(O)(CH2)2CH3] Acesulfamate [41] 296.51 8.0 Training257 2-hydroxyethyltrimethylammonium Dihydrogen phosphate [55] 355.24 9.4 Test258 Butyrolactam benzoate [56] 326.02 16.4 Training259 Didecyldimethylammonium tetrafluoroborate [57] 314.67 4.7 Training260 Hamine 1622(benzethonium) nitrate [57] 417.01 16.4 Training261 N,N,N0,N0,N00-Pentamethyl-N00-butyl-guanidinium nitrate [58] 317.23 8.1 Training262 1,3-Dimethyl-2-(N-propyl ammonium) imidazolidine perchlorate [58] 319.46 14.4 Training263 1,3-Dimethyl-2-(N-methyl-N-propyl ammonium)imidazolidine perchlorate [58] 314.04 0.6 Test264 1,3-Dimethyl-2-(N-methyl-N-propyl ammonium)imidazolidine nitrate [58] 307.99 1.3 Training265 1,3-Dimethyl-2-(N-methyl-N-butyl ammonium)imidazolidine perchlorate [58] 310.65 3.2 Test266 1,3-Dimethyl-2-(N-methyl-N-butyl ammonium)imidazolidine nitrate [58] 304.60 8.7 Test267 1,3-Dimethyl-3,4,5,6-tetrahydro-2-(N-methyl-N-propyl

ammonium)pyrimidine nitrate[58] 311.03 5.8 Training

268 1,3-Dimethyl-3,4,5,6-tetrahydro-2-(N-methyl-N butyl ammonium)pyrimidineperchlorate

[58] 311.96 11.2 Training

269 1,3-Dimethyl-3,4,5,6-tetrahydro-2-(N-methyl-N butyl ammonium)pyrimidinenitrate

[58] 305.91 9.6 Training

270 Tetrahydro-3,5-dimethyl-4-(N-methyl-N-propylammonium)-1,3,5-oxadiazine perchlorate

[58] 304.68 17.0 Test

271 Tetrahydro-3,5-dimethyl-4-(N-methyl-N-propylammonium)-1,3,5-oxadiazine nitrate

[58] 298.63 11.7 Training

272 Pentahexyloxytriphenylene guanidinium chloride [12] 371.97 16.5 Training273 Tetraethylphosphonium 2,2,2-trifluoro-N-(trifluoromethylsulfonyl)acetamide [21] 308.96 5.8 Training274 Tridecylmethylphosphonium chloride [59] 359.93 3.3 Training275 Tridecylmethylphosphonium bromide [59] 368.72 0.1 Training276 Tridecylmethylphosphonium nitrate [59] 339.17 1.9 Training277 Trihexyl-tetradecylphosphonium tetrafluoroborate [60] 332.70 6.8 Training278 Trihexyl-tetradecylphosphonium Trihexyl-tetradecylphosphonium [60] 357.79 14.4 Training279 Ethyltrihexylphosphonium bromide [60] 336.59 1.2 Test280 Butyltrihexylphosphonium bromide [60] 340.13 12.2 Training281 Tetrahexylphosphonium bromide [60] 348.61 1.6 Training282 Hexyltrimethylphosphonium bis((trifluoromethyl)sulfonyl)imide [22] 258.68 12.1 Training283 Hexyltrimethylphosphonium


284 Triphenyl(4-chlorosulfonylbutyl)phosphonium trifluoromethanesulfonate [61] 408.89 12.6 Training285 triethylbutylphosphonium bis((trifluoromethyl)sulfonyl)imide [35] 277.16 15.5 Training286 Triethylamylphosphonium bis((trifluoromethyl)sulfonyl)imide [35] 275.74 5.0 Test287 Triethyldodecylphosphonium bis((trifluoromethyl)sulfonyl)imide [35] 302.35 5.7 Training288 Triethyl(methoxymethyl)phosphonium bis((trifluoromethyl)sulfonyl)imide [35] 272.57 5.1 Training289 Triethyl(2-methoxyethyl)phosphonium bis((trifluoromethyl)sulfonyl)imide [35] 278.75 1.6 Training290 Hexadecyltributylphosphonium bromide [62] 363.87 9.9 Training291 O-ethyl-tetramethyluronium tris(pentafluoroethyl)trifluorophosphate [63] 277.95 8.9 Test292 S-ethyl-tetramethylthiouronium tris(pentafluoroethyl)trifluorophosphate [63] 290.63 6.4 Training293 1-(2-Methoxyethyl)-3-methylimidazolium chloride [64] 303.71 10.2 Training294 1-(2-Methoxyethyl)-3-methylimidazolium trifluoromethyltrifluoroborate [12] 268.76 2.3 Training295 1-(2-Methoxyethyl)-3-methylimidazolium pentafluoroethyltrifluoroborate [12] 263.86 0.1 Test296 1-(2-Methoxyethyl)-3-methylimidazolium trifluoromethanesulfonate [12] 280.98 6.4 Training297 1-(2-Methoxyethyl)-3-methylimidazolium hexafluorophosphate [12] 298.85 0.1 Training298 1-Methoxymethyl-3-methylimidazolium chloride [12] 302.73 4.3 Test299 1-Methoxymethyl-3-methylimidazolium trifluoromethyltrifluoroborate [12] 267.78 7.7 Training300 1-Methoxymethyl-3-methylimidazolium pentafluoroethyltrifluoroborate [12] 262.88 4.3 Test301 1-Methyl-3-(1,1,2,2-tetrafluoroethyl) imidazolium iodine [65] 376.05 9.0 Training302 1-Methyl-3-(1,1,2,2-tetrafluoroethyl) imidazolium tetrafluoroborate [65] 323.77 4.0 Test303 1-Methyl-3-(1,1,2,2-tetrafluoroethyl) imidazolium


304 1-Ethyl-3-(1,1,2,2-tetrafluoroethyl)imidazolium iodine [65] 367.87 1.3 Training305 1-Ethyl-3-(1,1,2,2-tetrafluoroethyl)imidazolium tetrafluoroborate [65] 315.59 5.9 Training306 1-Ethyl-3-(1,1,2,2-tetrafluoroethyl)imidazolium


307 1,3-Dimethylimidazolium chloride [66] 363.09 8.8 Test308 1-Butyl-3-methylimidazolium chloride [66] 302.94 10.4 Training309 1-Propyl-3-(1,1,2,2-tetrafluoroethyl)imidazolium iodine [65] 349.93 0.1 Test310 1,3-Dimethylimidazolium bromide [67] 371.89 2.8 Training311 1-Butyl-3-methylimidazolium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [8] 318.06 15.7 Training312 1-Butyl-3-methylimidazolium tetrakis

((4-dimethyl-(3,3,3-trifluoropropyl)-silyl)phenyl)borate[12] 435.07 15.4 Training

313 1-Butyl-3-methylimidazolium pentafluoroethyltrifluoroborate [12] 263.09 13.8 Training314 1-Butyl-3-methylimidazolium bis ((trifluoromethyl)sulfonyl)imide [68] 271.75 2.9 Training315 1-Butyl-3-(1,1,2,2-tetrafluoroethyl)imidazolium iodine [65] 350.63 1.3 Test316 1-Butyl-3-methylimidazolium dicyanamide [29] 261.07 2.3 Training317 1-Butyl-3-methylimidazolium pentyl sulfate [6] 240.44 6.1 Training318 1-Butyl-3-methylimidazolium 4,4,5,5,5-pentafluoropentyl sulfate [6] 266.14 3.1 Training319 1-Butyl-3-methylimidazolium methylsulfate [29] 246.40 2.7 Training320 1-Butyl-3-methylimidazolium trifluoromethanesulfonate [69] 280.21 2.1 Test321 1-(1-(R)-Ethoxycarbonyl-ethyl)-3-methylimidazolium



Table 2 (Continued)


322 1-(1-(R)-Ethoxycarbonyl-ethyl)-3-methylimidazoliumtrifluoromethanesulfonate

[12] 301.65 12.9 Training

323 1-Butyl-3-methylimidazolium perfluorobutylsulfonate [29] 262.96 10.0 Training324 1-Butyl-3-methylimidazolium hexafluorophosphate [69] 298.08 4.9 Test325 1-Butyl-3-methylimidazolium trifluoroacetate [70] 273.41 17.3 Training326 1-Butyl-3-methylimidazolium acetate [29] 214.26 15.4 Training327 1-Butyl-3-methylimidazolium tetrachloroaluminate [29] 276.24 5.0 Training328 1,3-Dimethylimidazolium tetrafluoroborate [13] 333.15 11.5 Training329 1,3-Dimethylimidazolium trifluoromethyltrifluoroborate [71] 328.14 13.9 Training330 1,3-Dimethylimidazolium pentafluoroethyltrifluoroborate [71] 323.25 7.7 Training331 1,3-Dimethylimidazolium (heptafluoro-n-propyl) trifluoroborate [71] 318.38 12.0 Test332 1,3-Dimethylimidazolium (nonafluoro-n-butyl) trifluoroborate [71] 313.54 8.4 Training333 1,3-Didodecyoxymethylimidazolium tetrafluoroborate [12] 313.72 10.7 Training334 1-(2-Hydroxyethyl)-3-methylimidazolium hexafluorophosphate [72] 316.69 6.9 Test335 Methyl 1-methylimidazolium-3-acetate hexafluorophosphate [73] 320.45 8.2 Training336 1-sec-Butyl-3-methylimidazolium perfluorobutylsulfonate [74] 280.57 11.0 Training337 1,3-Dimethylimidazolium bis((trifluoromethyl)sulfonyl)imide [29] 331.90 12.5 Training338 1-Trimethylsilyl-2-(oxoethyl-N methylimidazolium) iodine [75] 345.94 1.1 Training339 1-Trimethylsilyl-2-(oxoethyl-Nfluoroethylimidazolium) bromide [75] 340.23 14.8 Training340 1-Trimethylsilyl-2-(oxoethyl-N-30,30,30-trifluoropropylimidazolium) iodine [75] 381.26 6.1 Training341 1-[1-(Phenyl-chromium tricarbonyl)methyl]-3-methylimidazolium


342 1,3-Dimethylimidazolium trifluoromethanesulfonate [76] 340.36 9.0 Training343 1-Methylnitrile-3-methylimidazolium tetrafluoroborate [77] 312.13 1.3 Training344 1-Methylnitrile-3-methylimidazolium hexafluorophosphate [77] 337.22 4.0 Test345 1-Ethylnitrile-3-methylimidazolium chloride [77] 312.77 3.2 Test346 1-Ethylnitrile-3-methylimidazolium tetrafluoroborate [77] 282.83 3.5 Training347 1-Ethylnitrile-3-methylimidazolium hexafluorophosphate [77] 307.92 0.1 Training348 1-Propylnitrile-3-methylimidazolium chloride [77] 306.77 13.1 Training349 1-Propylnitrile-3-methylimidazolium 3-(trifluoroborate)-butylnitrile [78] 222.85 13.4 Training350 1-Propylnitrile-3-methylimidazolium hexafluorophosphate [77] 301.91 13.3 Training351 1-Butylnitrile-3-methylimidazolium chloride [77] 305.88 0.2 Test352 1,3-Dimethylimidazolium tosylate [79] 324.74 12.8 Training353 1-butyl-3-[2-(diethoxyphosphinyl) ethyl]-1H-imidazolium tetrafluoroborate [80] 255.30 14.5 Training354 1-butyl-3-[3-(diethoxyphosphinyl) propyl]-1H-imidazolium tetrafluoroborate [80] 228.05 9.2 Training355 1-butyl-3-[3-(diethoxyphosphinyl) propyl]-1H-imidazolium

hexafluorophosphate[80] 253.14 14.7 Test

356 1-Hexyl-3-[3-(diethoxyphosphinyl) propyl]-1H-imidazoliumtetrafluoroborate

[80] 228.72 15.7 Training

357 1-Octyl-3-[3-(diethoxyphosphinyl) propyl]-1H-imidazolium tetrafluoroborate [80] 238.25 14.2 Training358 1,3-Dimethylimidazolium trifluoroacetate [76] 333.57 2.6 Test359 1-Amyl-3-methylimidazolium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [12] 317.31 10.7 Test360 1-SF5(CF2)2(CH2)2-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [14] 243.35 11.8 Training361 1-Amyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [12] 271.00 2.6 Training362 1-SF5(CF2)2(CH2)4-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [14] 241.35 11.5 Training363 1-Butyl-3-ethylimidazolium bis((trifluoromethyl)sulfonyl)imide [29] 280.31 5.7 Training364 3-Methyl-1-[3-morpholinedithiocarbamate-propyl]-imidazolium


365 1-Butyl-3-ethylimidazolium trifluoromethanesulfonate [29] 288.77 4.9 Training366 1-Butyl-3-ethylimidazolium perfluorobutylsulfonate [29] 271.52 7.7 Training367 3-Methyl-1-[3-pyridinedithiocarbamate-propyl]-imidazolium


368 3-Methyl-1-[3-imidazoledithiocarbamate-propyl]-imidazoliumhexafluorophosphate

[81] 331.16 16.6 Training

369 3-Methyl-1-(3-bromopropyl)-imidazolium hexafluorophosphate [81] 319.33 0.4 Training370 3-Methyl-1-(N-butylcarbamoylmethyl) imidazolium hexafluorophosphate [73] 298.83 11.4 Training371 3-Methyl-1-(N-butyl-N-methylcarbamoylmethyl) imidazolium


372 3-Methyl-1-(N,N-diethylcarbamoylmethyl) imidazolium bromide [73] 338.23 0.3 Training373 3-Methyl-1-(N,N-diethylcarbamoylmethyl) imidazolium

bis((trifluoromethyl)sulfonyl)imide[73] 298.25 5.7 Test

374 3-Methyl-1-(N,N-diethylcarbamoylmethyl) imidazolium hexafluorophosphate [73] 324.58 3.7 Test375 N-(2-hydroxyethyl)-N-methyl morphorinium bromide [72] 378.75 10.5 Test376 N-(2-hydroxyethyl)-N-methyl morphorinium hexafluorophosphate [72] 365.10 15.8 Training377 1-Methyl-3-propylcarboxylimidazolium 3-(trifluoroborate)-butylnitrile [78] 250.71 16.9 Training378 N-propyl-N-methylmorpholinium perchlorate [82] 322.97 11.3 Training379 N-propyl-N-methylmorpholinium nitrate [83] 316.92 4.3 Test380 N-propyl-N-methylmorpholinium hexafluorophosphate [83] 332.82 7.3 Training381 N-(3-fluoropropyl)-N-methylmorpholinium trifluoromethanesulfonate [83] 313.33 8.2 Training382 N-(3-fluoropropyl)-N-methylmorpholinium hexafluorophosphate [83] 331.20 6.2 Training383 N-((trifluoroethoxy)ethyl)-N methylmorpholinium hexafluorophosphate [83] 369.82 7.1 Training384 N-(2,2,3,3,4,4,5,5-octafluoro-1-pentoxyethyl)-N methylmorpholinium


385 Morpholinium 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate [52] 333.94 0.4 Training386 Morpholinium 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedionate [52] 342.85 0.7 Training387 N-methyl-N-ethylmorpholinium bis((trifluoromethyl)sulfonyl)imide [84] 343.27 13.5 Test388 1,3-Dipropargylimidazolium tetrafluoroborate [85] 325.19 4.4 Training


Table 2 (Continued)


389 N-methyl-N-butylmorpholinium tetrafluoroborate [86] 307.44 9.4 Training390 N-methyl-N-butylmorpholinium (heptafluoro-n-propyl)trifluoroborate [86] 292.67 14.5 Training391 N-methyl-N-butylmorpholinium (nonafluoro-n-butyl)trifluoroborate [86] 287.83 17.6 Training392 N-methyl-N-butylmorpholinium bis((trifluoromethyl)sulfonyl)imide [86] 306.19 0.6 Training393 N-methoxyethyl-N-methylmorphonium tetrafluoroborate [86] 325.86 9.0 Training394 N-methoxyethyl-N-methylmorphonium trifluoromethyltrifluoroborate [86] 320.85 17.0 Training395 N-methoxyethyl-N-methylmorphonium bis((trifluoromethyl)sulfonyl)imide [86] 324.61 9.4 Training396 1.3-Dibutylnitrileimidazolium 3-(trifluoroborate)-butylnitrile [78] 238.45 17.3 Training397 1,3-Dipropylcarboxylimidazolium 3-(trifluoroborate)-butylnitrile [78] 296.94 4.6 Training398 1-[2-benzoxylpropyl]-3-methylimidazolium bromide [87] 369.59 11.9 Test399 1-[2-benzoxylpropyl]-3-methylimidazolium tetrafluoroborate [87] 330.86 5.3 Training400 1-[2-benzoxylpropyl]-3-methylimidazolium hexafluorophosphate [87] 355.94 2.5 Training401 1-(2,3-Dibromopropyl)-3-methylimidazolium hexafluorophosphate [88] 326.19 5.1 Training402 1-(2,3-Dibromopropyl)-3-methylimidazolium hexafluoroantimonate [88] 344.60 2.1 Training403 1,2-Dimethylimidazolium chloride [10] 380.87 16.1 Training404 1,2-Dimethylimidazolium bromide [10] 389.66 13.2 Test405 1-Hexyl-3-methylimidazolium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [8] 319.51 10.0 Training406 1-Hexyl-3-methylimidazolium pentafluoroethyltrifluoroborate [12] 264.54 0.5 Training407 1-Hexyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [3] 273.20 2.7 Training408 1,2-Dimethylimidazolium perchlorate [10] 366.16 8.6 Training409 1-Hexyl-3-methylimidazolium trifluoromethanesulfonate [29] 281.66 6.8 Training410 1,3-Divaleryleneimidazolium cloride [85] 377.21 11.6 Training411 1-Hexyl-3-methylimidazolium tris (pentafluoroethyl)trifluorophosphate [12] 256.06 14.7 Test412 1,3-Dibenzylimidazolium Tosylate [34] 397.06 2.7 Training413 1,2-Dimethylimidazolium bis((perfluoroethane)sulfonyl)imide [10] 335.56 16.5 Training414 1,2-Dimethylimidazolium nitrate [10] 360.11 0.8 Training415 1-Heptyl-3-methylimidazolium

tetrakis(3,5-bis(trifluoromethyl)phenyl)borate[8] 324.47 5.2 Test

416 1,2-Dimethylimidazolium trifluoromethanesulfonate [10] 358.13 8.7 Training417 1-Heptyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [12] 278.16 0.7 Training418 1,2-Dimethylimidazolium hexafluorophosphate [10] 376.01 3.1 Test419 1,3-Dibutylimidazolium chloride [12] 317.15 3.4 Test420 1-Benzyl-3-methylimidazolium bromide [67] 379.55 4.9 Training421 1-Benzyl-3-methylimidazolium trifluoromethanesulfonate [89] 348.03 16.0 Training422 1-Benzyl-3-methylimidazolium hexafluorophosphate [90] 365.90 9.2 Training423 1-(4-Methoxyphenyl)-3-methylimidazolium trifluoromethanesulfonate [12] 326.50 2.6 Training424 1-Octyl-3-methylimidazolium chloride [91] 312.43 9.5 Training425 1-Octyl-3-methylimidazolium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [8] 327.54 5.9 Training426 2,4,5-Trimethyltetrazolium perchlorate [92] 376.48 7.3 Training427 4,5-Dimethyl-1-aminotetrazolium iodine [93] 407.80 3.5 Training428 4,5-Dimethyl-1-aminotetrazolium perchlorate [93] 370.75 14.4 Training429 4,5-Dimethyl-2-aminotetrazolium iodine [93] 428.95 8.0 Training430 4,5-Dimethyl-2-aminotetrazolium perchlorate [93] 391.90 5.1 Training431 4,5-Dimethyl-2-aminotetrazolium nitrate [93] 385.85 5.1 Training432 1-Phenethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [12] 339.73 9.5 Training433 1-Phenethyl-3-methylimidazolium hexafluorophosphate [90] 366.06 2.7 Training434 1-Ethyl-3-methylimidazolium bromide [67] 328.02 3.0 Test435 1-Ethyl-3-methylimidazolium iodine [38] 341.56 3.0 Training436 1-Ethyl-3-methylimidazolium thiocyanate [29] 286.86 7.4 Training437 1-(1-Heptoxymethyl)-3-methylimidazolium hexafluorophosphate [94] 292.97 5.5 Training438 1-Ethyl-3-methylimidazolium tetrafluoroborate [95] 289.28 0.4 Training439 1-Phenylethanoyl-3-propylimidazolium bromide [67] 368.33 12.7 Test440 1-Ethyl-3-methylimidazolium trifluoromethyl trifluoroborate [71] 284.28 12.3 Test441 1-Ethyl-3-methylimidazolium pentafluoroethyltrifluoroborate [96] 279.38 2.7 Training442 1-Ethyl-3-methylimidazolium (heptafluoron-n-propyl)trifluoroborate [96] 274.51 2.4 Training443 1-Ethyl-3-methylimidazolium (nonafluoron-n-butyl)trifluoroborate [71] 269.67 0.2 Training444 1-Ethyl-3-methylimidazolium n-pentyltrifluoroborate [12] 239.00 17.3 Test445 1-Ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [97] 288.03 10.3 Training446 1-Ethyl-3-methylimidazolium bis(nonafluorobutane-1-sulfonyl)imide [74] 256.94 13.8 Training447 1-Ethyl-3-methylimidazolium bis(fluorosulfonyl) imide [98] 305.34 17.4 Test448 1-Ethyl-3-methylimidazolium bis((perfluoroethane)sulfonyl)imide [99] 273.92 4.9 Test449 1-Ethyl-3-methylimidazolium dicyanoamide [71] 277.35 10.0 Training450 1-Ethyl-3-methylimidazolium


451 3-Propoxymethyl-1-butoxymethylimidazolium hexafluorophosphate [94] 303.78 5.1 Training452 1-Ethyl-3-methylimidazolium nitrite [100] 302.82 7.7 Test453 1-Ethyl-3-methylimidazolium nitrate [101] 298.46 4.1 Test454 1-Ethyl-3-methylimidazolium sulfate [100] 303.88 11.4 Training455 1-Ethyl-3-methylimidazolium 2,2,3,3,4,4,5,5-octafluoropentyl sulfate [12] 277.83 8.1 Training456 1-Ethyl-3-methylimidazolium methylsulfate [29] 262.69 5.6 Training457 1-Ethyl-3-methylimidazolium trifluoromethan esulfonate [29] 296.49 12.2 Training458 1-Ethyl-3-methylimidazolium perfluorobutylsulfonate [100] 279.24 7.3 Test459 1-Nonyl-3-methylimidazolium hexafluorophosphate [90] 309.57 7.8 Training460 1-Ethyl-3-methylimidazolium hexafluorophosphate [100] 314.37 5.1 Training461 1-Ethyl-3-methylimidazolium tris (pentafluoroethyl)trifluorophosphate [63] 270.90 14.7 Training462 1-Ethyl-3-methylimidazolium trifluoroacetate [100] 289.70 11.8 Training463 1-Ethyl-3-methylimidazolium acetate [29] 230.55 8.9 Training


Table 2 (Continued)


464 1-Hydrocinnamyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [12] 330.88 3.0 Test465 1-Methyl-3-ethylimidazolium hydrogen phthalate [102] 290.78 1.7 Training466 1-Hydrocinnamyl-3-methylimidazolium hexafluorophosphate [12] 357.21 9.9 Training467 1-Ethyl-3-methylimidazolium tris(trifluoromethylsulfonyl)methide [38] 283.44 9.2 Test468 1-Ethyl-3-methylimidazolium tricyanomethanide [12] 269.42 2.4 Training469 1,3-Di(1-butoxymethyl)imidazolium hexafluorophosphate [94] 297.84 9.8 Test470 1-Ethyl-3-methylimidazolium tetrachloroaluminate [103] 292.52 4.4 Training471 1-Ethyl-3-methylimidazolium hexafluoroarsenate [104] 331.45 1.7 Training472 1-Decyl-3-methylimidazolium chloride [91] 319.17 2.6 Test473 1-Decyl-3-methylimidazolium tetrafluoroborate [13] 289.23 7.5 Training474 1-Decyl-3-methylimidazolium tetrakis (3,5-bis(trifluoromethyl)phenyl)borate [8] 334.29 6.7 Training475 1-Decyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [90] 287.98 6.2 Training476 1-Decyl-3-methylimidazolium hexafluorophosphate [100] 314.31 2.3 Training477 N-propyl-N-methyloxazolidinium bis((trifluoromethyl)sulfonyl)imide [83] 290.14 8.5 Training478 N-propyl-N-methyloxazolidinium hexafluorophosphate [83] 316.47 0.7 Training479 N-butyl-N-methyloxazolidinium tetrafluoroborate [86] 292.64 12.1 Training480 N-butyl-N-methyloxazolidinium pentafluoroethyltrifluoroborate [86] 282.73 5.0 Training481 N-butyl-N-methyloxazolidinium (heptafluoro-n-propyl)trifluoroborate [86] 277.87 14.8 Training482 N-butyl-N-methyloxazolidinium (nonafluoro-n-butyl)trifluoroborate [86] 273.03 16.5 Training483 N-butyl-N-methyloxazolidinium bis((trifluoromethyl)sulfonyl)imide [86] 291.39 2.2 Training484 N-methoxyethyl-N-methyloxazolidinium pentafluoroethyltrifluoroborate [86] 298.47 8.9 Training485 N-methoxyethyl-N-methyloxazolidinium


486 N-methoxyethyl-N-methyloxazolidinium (nonafluoro-n-butyl)trifluoroborate [86] 288.77 0.8 Training487 1-Ethyl-2-methylimidazolium chloride [10] 372.50 17.4 Training488 1-Ethyl-2-methylimidazolium bromide [10] 381.29 8.6 Training489 1-Undecyl-3-methylimidazolium tetrafluoroborate [12] 292.28 0.8 Training490 1-Ethyl-2-methylimidazolium nitrate [10] 351.74 1.0 Test491 1-Ethyl-2-methylimidazolium trifluoromethanesulfonate [10] 349.77 14.2 Training492 1-Dodecyl-3-methylimidazolium chloride [91] 326.20 11.8 Training493 1-Dodecyl-3-methylimidazolium tetrafluoroborate [13] 296.26 1.1 Training494 1-Dodecyl-3-methylimidazolium tetrakis

(3,5-bis(trifluoromethyl)phenyl)borate[8] 341.32 1.1 Training

495 1-Dodecyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [105] 295.01 1.8 Training496 1-Dodecyl-3-methylimidazolium 1-Dodecyl-3-methylimidazolium [105] 303.47 3.0 Training497 1-Dodecyl-3-methylimidazolium hexafluorophosphate [106] 321.35 0.6 Training498 1-Trimdecyl-3-methylimidazolium tetrafluoroborate [13] 301.56 6.4 Test499 1-Tetradecyl-3-methylimidazolium chloride [105] 333.55 14.0 Test500 1-Tetradecyl-3-methylimidazolium bromide [107] 342.34 4.6 Test501 1-Tetradecyl-3-methylimidazolium tetrafluoroborate [108] 303.61 2.4 Training502 1-Tetradecyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [105] 302.36 1.7 Training503 1-Tetradecyl-3-methylimidazolium trifluoromethanesulfonate [105] 310.82 3.8 Training504 1-Tetradecyl-3-methylimidazolium hexafluorophosphate [108] 328.69 5.0 Test505 1-Pentadecyl-3-methylimidazolium tetrafluoroborate [13] 309.08 5.9 Test506 1-Hexadecyl-3-methylimidazolium chloride [105] 343.56 9.0 Training507 1-Hexadecyl-3-methylimidazolium bromide [105] 352.35 12.4 Training508 1-Hexadecyl-3-methylimidazolium tetrafluoroborate [108] 313.62 1.7 Training509 1-Hexadecyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [105] 312.37 0.9 Training510 1-Hexadecyl-3-methylimidazolium trifluoromethanesulfonate [105] 320.83 3.1 Training511 1-Hexadecyl-3-methylimidazolium hexafluorophosphate [109] 338.70 2.7 Training512 1-Octadecyl-3-methylimidazolium chloride [105] 348.69 6.8 Training513 1-Octadecyl-3-methylimidazolium tetrafluoroborate [13] 318.74 6.2 Training514 1-Octadecyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [105] 317.50 0.1 Training515 1-Octadecyl-3-methylimidazolium trifluoromethanesulfonate [105] 325.95 3.9 Training516 1-Octadecyl-3-methylimidazolium hexafluorophosphate [9] 343.83 2.6 Test517 1-SF5(CF2)2(CH2)2-pyridazinium bis((trifluoromethyl)sulfonyl)imide [14] 261.13 0.8 Training518 1-Cosyl-3-methylimidazolium bromide [105] 363.34 9.0 Training519 1-Trifluoroethyl-3-methylimidazolium trifluoromethanesulfonate [12] 318.19 0.0 Training520 1,3-Diethylimidazolium bis((trifluoromethyl) sulfonyl)imide [76] 306.03 6.6 Training521 1,3-Diethylimidazolium trifluoromethanesulfonate [29] 314.49 6.2 Training522 Glycinium chloride [110] 390.05 15.0 Training523 Glycinium tetrafluoroborate [110] 360.11 7.5 Training524 Glycinium nitrate [110] 369.29 3.9 Test525 Glycinium hexafluorophosphate [110] 385.19 3.0 Training526 Alaninium tetrafluoroborate [110] 367.17 4.6 Training527 Alaninium nitrate [110] 376.36 12.9 Training528 di(Alaninium) sulfate [110] 381.77 7.8 Training529 Alaninium trifluoroacetate [110] 367.59 3.5 Training530 Prolinium tetrafluoroborate [110] 356.10 2.0 Training531 di(Prolinium) sulfate [110] 370.69 1.5 Test532 Prolinium trifluoroacetate [110] 356.51 1.5 Training533 Valinium nitrate [110] 388.84 4.5 Training534 Isoleucinium nitrate [110] 355.53 6.0 Training535 Protonated methyl 1-amino-acetate nitrate [110] 353.32 11.4 Test536 Protonated ethyl 1-amino-acetate nitrate [110] 325.91 1.2 Training537 Protonated methyl 1-amino-propionate thiocyanate [110] 335.19 0.0 Training538 Protonated methyl 1-amino-propionate nitrate [110] 346.80 3.8 Training


Table 2 (Continued)


539 Protonated methyl 1-amino-propionate L-lactate [110] 295.37 5.1 Training540 Protonated methyl 1-amino-2-hydroxy-propionate nitrate [110] 334.65 11.5 Training541 Protonated ethyl 1-amino-propinate L-lactate [110] 280.58 13.1 Test542 Protonated methyl 1-amino-isovalerate nitrate [110] 343.55 8.2 Test543 Leucinium nitrate [110] 352.37 1.2 Training544 Protonated methyl 1-amino-2-phenylpropionate nitrate [110] 398.86 9.2 Test545 Methyl 1-(N-benzoyl amino)-2-(1,3-di(n-propyl) imidazolium)-propionate

bromide[111] 364.30 16.7 Training

546 Methyl1-(N-tert-butoxycarbonylamino)-2-(1,3-di(iso-propyl)imidazolium-propinateiodine

[111] 381.99 16.4 Test

547 1-Propyl-3-methylimidazolium chloride [66] 301.07 9.6 Training548 1-Propyl-3-methylimidazolium tetrafluoroborate [112] 271.13 5.8 Training549 1-Propyl-3-methylimidazolium trifluoromethyltrifluoroborate [12] 266.12 5.5 Training550 1-propyl-3-methylimidazolium pentafluoroethyltrifluoroborate [12] 261.22 13.0 Training551 1-Propyl-3-methylimidazolium (heptafluoro-n-propyl)trifluoroborate [12] 256.36 4.4 Test552 1-Propyl-3-methylimidazolium (nonafluoro-n-butyl)trifluoroborate [12] 251.52 3.7 Training553 1-Propyl-3-methylimidazolium perfluorobutylsulfonate [12] 261.09 14.7 Test554 1-Propyl-3-methylimidazolium hexafluorophosphate [101] 296.21 5.4 Training555 1-Isopropyl-3-methylimidazolium iodine [12] 355.79 8.1 Training556 1-Isopropyl-3-methylimidazolium bis(nonafluorobutane-1-sulfonyl)imide [12] 271.17 10.0 Training557 1-Isopropyl-3-methylimidazolium hexafluorophosphate [38] 328.60 12.4 Training558 1-Butyl-2,3-dimethylimidazolium tetrafluoroborate [113] 299.90 4.1 Training559 1-Butyl-2,3-dimethylimidazolium bis((trifluoromethyl)sulfonyl)imide [41] 298.65 13.0 Training560 1-Butyl-2,3-dimethylimidazolium 4,4,5,5,5-pentafluoropentyl sulfate [6] 293.05 2.6 Training561 1-Butyl-2,3-dimethylimidazolium 2,2,3,3,4,4,5,5-octafluoropentyl sulfate [6] 288.45 11.4 Training562 1-Butyl-2,3-dimethylimidazolium perfluorobutylsulfonate [114] 289.86 12.7 Training563 1-Butyl-2,3-dimethylimidazolium hexafluorophosphate [113] 324.99 3.8 Test564 1-Butyl-2,3-dimethylimidazolium hexafluoroantimonate [113] 343.40 8.2 Training565 2,4,5-Trimethylimidazolium chloride [12] 419.92 10.1 Training566 1,2,3-Trimethylimidazolium chloride [66] 398.67 13.7 Training567 1,2-Dimethyl-3-ethylimidazolium bromide [38] 362.73 12.4 Training568 1,2-Dimethyl-3-ethylimidazolium bis ((trifluoromethyl)sulfonyl)imide [76] 322.75 10.2 Training569 1,2-Dimethyl-3-ethylimidazolium bis((perfluoroethane)sulfonyl)imide [38] 308.63 3.5 Training570 1,2-Dimethyl-3-ethylimidazolium trifluoromethanesulfonate [76] 331.21 13.3 Training571 1,2-Dimethyl-3-ethylimidazolium trifluoroacetate [76] 324.41 2.3 Training572 1-Ethyl-3,5-dimethylimidazolium bis ((trifluoromethyl)sulfonyl)imide [76] 305.77 13.2 Training573 1-Ethyl-3,5-dimethylimidazolium trifluoromethanesulfonate [76] 314.22 12.6 Training574 2,3-Dimethyl-1-ethylimidazolium bis (trifluoromethylsulfonyl)imide [29] 321.86 9.8 Test575 1-Propylnitrile-2,3-dimethylimidazolium chloride [77] 332.46 12.1 Training576 1-Propylnitrile-2,3-dimethylimidazolium tetrafluoroborate [77] 302.51 3.4 Training577 1-Propylnitrile-2,3-dimethylimidazolium hexafluorophosphate [77] 327.60 8.5 Training578 1-Methyl-2,3-trimethyleneimidazolium bis((trifluoromethyl)sulfonyl)imide [115] 339.24 4.7 Training579 1-Ethyl-2,3-dimethylimidazolium benzoate [7] 315.02 9.0 Test580 1-Hexyl-2,3-dimethylimidazolium bis((trifluoromethyl)sulfonyl)imide [3] 294.93 10.0 Training581 1,3-diethyl-5-methylimidazolium trifluoromethanesulfonate [76] 328.28 6.5 Training582 Cr(CO)3(h6-C6H5CH2MMIM) bis((trifluoromethyl)sulfonyl)imides [46] 346.47 1.6 Training583 1,3,10,30-Tetramethyl-2,20-biimidazolium

di[bis(trifluoromethanesulfonyl)amide][116] 329.25 10.1 Training

584 1,3,10,30-Tetramethyl-2,20-biimidazolium bis(hexafluorophosphate) [116] 355.58 8.9 Training585 1,10-Dibutyl-3,30-dimethylbiimidzaolium bis(hexafluorophosphate) [116] 312.11 10.4 Training586 1,2-Dimethyl-3-propylimidazolium bis ((trifluoromethyl)sulfonyl)imide [29] 302.27 4.9 Training Training587 1,2-dimethyl-3-propylimidazolium bis((perfluoroethane)sulfonyl)imide [38] 288.15 6.2 Training588 1,2-dimethyl-3-propylimidazolium hexafluorophosphate [117] 328.60 6.4 Training589 1,2-diethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [76] 294.96 2.1 Training590 1-Methyl-2,3-tetramethyleneimidazolium

bis(trifluoromethanesulfonyl)amide[115] 313.55 1.8 Training

591 1,2,3-Trimethyl-5-nitroimidazolium nitrate [92] 370.20 14.7 Test592 1-Ethyl-2,3-dimethyl-5-nitroimidazolium nitrate [92] 332.15 1.8 Test593 1,2,3,4,5-Quinarymethylimidazolium iodine [38] 450.94 7.2 Test594 1,2,3,4,5-Quinarymethylimidazolium bis((trifluoromethyl)sulfonyl)imide [38] 397.41 1.6 Training595 1,2,3,4,5-Quinarymethylimidazolium hexafluorophosphate [38] 423.74 3.5 Training596 1,4-Bis(3-tetradecylimidazolium-1-yl) butane bromide [107] 341.36 3.1 Training597 1,10-(2,2,3,3,4,4-Hexafluoropentane-1,5-diyl)

1,10-(2,2,3,3,4,4-Hexafluoropentane-1,5-diyl)di[bis(trifluoromethanesulfonyl)amide]

[12] 305.92 5.1 Test

598 1,10-(2,2,3,3,4,4,5,5-Octafluorohexane-1,6-diyl)bis(3-butyl-1H-imidazolium-1-yl) di[bis(trifluoromethanesulfonyl)amide]

[12] 305.92 12.0 Training

599 1,10-(1,4-Phenylenebismethylene)bis(3-butyl-1H imidazolium-1-yl)di[bis(trifluoromethanesulfonyl)amide]

[12] 322.59 0.0 Training

600 1,10-(1,4-Phenylenebismethylene)bis(3-decyl-1H imidazolium-1-yl)di[bis(trifluoromethanesulfonyl)amide]

[12] 339.63 0.6 Training

601 1,10-(1,4-Phenylenebismethylene)bis(3-tetradecyl-1H-imidazolium-1-yl)di[bis(trifluoromethanesulfonyl) amide]

[12] 357.09 0.3 Training

602 1,10-(2,3,5,6-Tetrafluoro-1,4-phenylenebismethylene)bis(3-butyl-1H-imidazolium-1-yl)di[bis(trifluoromethanesulfonyl)amide]

[12] 327.70 5.1 Training


Table 2 (Continued)


603 1,4-Di-(1-methylimidazolium)-2,3-di(benzoyl oxygen)-butane dibromide [87] 412.19 9.4 Training604 1,4-Di-(1-methylimidazolium)-2,3-di(benzoyl oxygen)-butane

ditetrafluoroborate[87] 373.46 7.1 Training

605 1,4-Di-(1-methylimidazolium)-2,3-di(benzoyl oxygen)-butanedihexafluorophosphate

[87] 398.54 10.4 Training

606 1-Butyl-4-(1H,1H,2H,2H-perfluorohexyl)-1,2,4-triazoliumbis((trifluoromethyl)sulfonyl)imide

[118] 318.64 6.9 Training

607 1-Butyl-3-methylbenzotriazolium bis((trifluoromethyl)sulfonyl)imide [119] 302.69 0.2 Training608 1-Heptyl-4-(1H,1H,2H,2H-perfluorohexyl)-1,2,4-triazolium


609 1-Decyl-4-(1H,1H,2H,2H-perfluorohexyl)-1,2,4-triazoliumbis((trifluoromethyl)sulfonyl)imide

[118] 331.03 1.5 Training

610 1-Methyl-4-(1H,1H,2H,2H-perfluorooctyl)-1,2,4-triazoliumbis((trifluoromethyl)sulfonyl)imide

[118] 334.33 0.2 Training

611 1-Butyl-4-(1H,1H,2H,2H-perfluorooctyl)-1,2,4-triazoliumbis((trifluoromethyl)sulfonyl)imide

[118] 324.39 7.7 Training

612 1-Heptyl-4-(1H,1H,2H,2H-perfluorooctyl)-1,2,4-triazoliumbis((trifluoromethyl)sulfonyl)imide

[118] 327.42 10.9 Test

613 1-Heptyl-4-(1-fluoroethyl)-1,2,4-triazolium tetrafluoroborate [118] 293.36 9.8 Training614 1-Decyl-4-(1-fluoroethyl)-1,2,4-triazolium trifluoromethanesulfonate [118] 310.38 2.7 Training615 1-Benzyl-3-methylbenzotriazolium bromide [119] 429.01 3.8 Training616 1-Benzyl-3-methylbenzotriazolium bis((trifluoromethyl)sulfonyl)imide [119] 389.02 13.7 Training617 1-Benzyl-3-methylbenzotriazolium mesylate [119] 357.47 2.1 Training618 1-Benzyl-3-methylbenzotriazolium tosylate [119] 381.86 8.2 Training619 1-(2-Azidoethyl)-4-methyl-1,2,4-triazolium iodine [120] 334.38 2.2 Training620 1-Methyl-4-amino-1,2,4-triazolium perchlorate [93] 347.45 3.3 Training621 1-Methyl-4-amino-1,2,4-triazolium azide [121] 327.07 3.5 Training622 1-Methyl-4-amino-1,2,4-triazolium nitrate [93] 341.40 4.4 Training623 1-Methyl-3-azido-1,2,4-triazolium 4,5-dinitroimidazolate [122] 326.87 7.4 Training624 1-Methyl-3-azido-1,2,4-triazolium perchlorate [92] 337.66 2.9 Training625 1-Methyl-3-azido-1,2,4-triazolium nitrate [92] 331.61 2.2 Training626 5-Methyl-3-azido-1,2,4-triazolium nitrate [92] 330.01 15.6 Test627 3-Azido-1,2,4-triazolium 4,5-dinitroimidazolate [122] 349.31 4.3 Training628 3-Azido-1,2,4-triazolium nitrate [92] 354.05 15.7 Training629 3,5-Diazido-1,2,4-triazolium nitrate [92] 375.97 1.6 Training630 1,4-Dimethyl-3-azido-1,2,4-triazolium perchlorate [92] 309.75 9.2 Training631 1-Propyl-4-SF5(CF2)2(CH2)4-1,2,4-triazolium bis

((trifluoromethyl)sulfonyl)imide[14] 246.36 12.8 Training

632 1-Amino-1,2,4-triazolium perchlorate [93] 367.14 0.8 Test633 1-Amino-1,2,4-triazolium nitrate [93] 361.09 8.4 Training634 1-Methyl-4-(2-azidoethyl)-1,2,4-triazolium perchlorate [120] 302.88 9.9 Training635 4-Amino-1,2,4-triazolium 5-nitrotetrazolate [122] 334.21 10.9 Training636 4-Amino-1,2,4-triazolium 4,5-dinitroimidazolate [122] 347.23 15.3 Training637 4-Amino-1,2,4-triazolium 3-nitro-1,2,4-triazolate [122] 336.16 0.3 Training638 4-Amino-1,2,4-triazolium perchlorate [93] 358.02 0.5 Training639 4-Amino-1,2,4-triazolium nitrate [93] 351.97 2.9 Training640 1-Amino-4-methyl-1,2,4-triazolium perchlorate [93] 347.80 8.7 Training641 1,5-Diamino-1,2,4-triazolium perchlorate [93] 420.45 2.3 Training642 1,5-Diamino-1,2,4-triazolium nitrate [93] 414.40 4.1 Training643 2,3-Diamino-1,2,4-triazolium 4,5-dinitroimidazolate [122] 408.23 4.2 Test644 1-Methyl-1,2,4-triazolium 1-Methyl-1,2,4-triazolium [122] 351.63 6.3 Test645 1-Butyl-3-ethylbenzotriazolium hexafluorophosphate [123] 326.86 12.6 Training646 1,3-Dibutylbenzotriazolium bromide [123] 340.04 5.8 Training647 1,3-Dibutylbenzotriazolium tetrafluoroborate [123] 301.30 15.9 Test648 1,3-Dibutylbenzotriazolium hexafluorophosphate [123] 326.39 15.5 Training649 1-(3-Fluoropropyl)-3-trifluoromethyl-4,5-dimethyl-1,2,4-triazolium iodine [124] 361.99 6.7 Test650 1-(3-Fluoropropyl)-3-trifluoromethyl-4,5-1-(3-Fluoropropyl)-3-

trifluoromethyl-4,5-amide[124] 308.47 4.2 Training

651 1,4,5-Trimethyl-3-perfluorooctyl-1,2,4-triazolium perchlorate [124] 393.12 8.3 Training652 1,4,5-Trimethyl-3-perfluorooctyl-1,2,4-triazolium tetrafluoroborate [124] 377.89 1.8 Training653 1,4,5-Trimethyl-3-perfluorooctyl-1,2,4-triazolium


654 1,4,5-Trimethyl-3-trifluoromethyl-1,2,4-triazolium perchlorate [124] 400.27 0.2 Training655 1,4,5-Trimethyl-3-trifluoromethyl-1,2,4-triazolium tetrafluoroborate [124] 385.04 4.5 Test656 1,4,5-Trimethyl-3-trifluoromethyl-1,2,4-triazolium


657 1,4,5-Trimethyl-3-trifluoromethyl-1,2,4-triazolium trifluoromethanesulfonate [124] 392.25 4.4 Training658 1-(2-Azidoethyl)-1,2,4-triazolium nitrate [120] 313.74 15.7 Training659 1-Amino-3-methyl-1,2,3-triazolium azide [121] 337.88 4.6 Training660 1-Amino-3-methyl-1,2,3-triazolium nitrate [125] 352.21 1.9 Training661 1-Amino-3-ethyl-1,2,3-triazolium nitrate [125] 317.51 4.7 Test662 1-Amino-3-n-propyl-1,2,3-triazolium nitrate [125] 291.38 4.8 Training663 1-Amino-3-(2-propenyl)-1,2,3-triazolium nitrate [125] 307.46 9.4 Training664 1-Amino-3-n-butyl-1,2,3-triazolium nitrate [125] 290.86 9.4 Training665 1-(2-Bromoethyl)-4-amino-1,2,4-triazolium bromide [121] 345.50 14.5 Training666 1-(2-Azidoethyl)-4-amino-1,2,4-triazolium bromide [120] 335.50 6.3 Test667 1-Butyl-4-(3,3,3-trifluoropropyl)-1-Butyl-4-(3,3,3-trifluoropropyl)- [118] 304.38 0.6 Training


Table 2 (Continued)


668 N-methylpyrrolidinium trifluoroacetate [17] 337.74 8.5 Training669 N-methoxymethyl-N-methylpyrrolidinium tetrafluoroborate [86] 298.28 16.9 Training670 N-methoxymethyl-N-methylpyrrolidinium trifluoromethyltrifluoroborate [86] 293.27 9.0 Training671 N-methoxymethyl-N-methylpyrrolidinium pentafluoroethyltrifluoroborate [86] 288.37 3.6 Training672 N-methoxyethyl-N-methylpyrrolidinium tetrafluoroborate [86] 304.69 6.9 Training673 N-methoxyethyl-N-methylpyrrolidinium trifluoromethyltrifluoroborate [86] 299.68 16.5 Training674 N-methoxyethyl-N-methylpyrrolidinium pentafluoroethyltrifluoroborate [86] 294.78 9.1 Training675 N,N-dimethylpyrrolidinium bis((trifluoromethyl)sulfonyl)imide [12] 352.35 6.8 Training676 N,N-dimethylpyrrolidinium dicyanoamide [126] 341.67 12.0 Test677 N,N-dimethylpyrrolidinium bis(methylsulfonyl)imide [127] 323.10 3.2 Test678 N,N0-dimethylpyrrolidinium hydrogen maleate [102] 341.43 1.6 Training679 N,N0-dimethylpyrrolidinium hydrogen phthalate [102] 355.10 1.6 Training680 N-methyl-N-ethyl-pyrrolidinium bis((trifluoromethyl)sulfonyl)imide [24] 339.62 5.4 Training681 N-methyl-N-ethyl-pyrrolidinium mesylate [43] 308.06 1.6 Training682 N-methyl-N-ethyl-pyrrolidinium tosylate [43] 332.45 15.4 Training683 N-methyl-N-propyl-pyrrolidinium bis((trifluoromethyl)sulfonyl)imide [128] 312.83 9.7 Test684 N-methyl-N-butyl-pyrrolidinium tetrafluoroborate [129] 318.43 9.3 Training685 N-methyl-N-butyl-pyrrolidinium pentafluoroethyltrifluoroborate [86] 308.53 4.5 Test686 N-methyl-N-butyl-pyrrolidinium (heptafluoro-n-propyl)trifluoroborate [86] 303.66 6.9 Training687 N-methyl-N-butyl-pyrrolidinium (nonafluoro-n-butyl)trifluoroborate [86] 298.82 10.6 Training688 N-methyl-N-butyl-pyrrolidinium mesylate [43] 285.63 15.0 Training689 N-methyl-N-butyl-pyrrolidinium perfluorobutylsulfonate [130] 308.39 16.0 Training690 N-methyl-N-butyl-pyrrolidinium dihydrogen phosphate [55] 320.74 16.7 Training691 N-methyl-N-hexyl-pyrrolidinium dicyanoamide [126] 300.68 14.7 Test692 1-Methyl-1-octylpiperidinium tetrafluoroborate [129] 323.91 11.3 Training693 1-Methyl-1-octylpiperidinium trifluoromethanesulfonate [129] 331.12 3.4 Training694 N-methyl-N-propylpiperidinium bis((trifluoromethyl)sulfonyl)imide [131] 314.45 11.6 Training695 N-methyl-N-propylpiperidinium


696 2,2,6,6-Tetramethyl-4-aminopiperidinium1,1,1,5,5,5-hexafluoro-2,4-pentanedionate

[52] 389.18 7.8 Training

697 2,2,6,6-Tetramethyl-4-aminopiperidinium4,4,4-trifluoro-1-(2-furyl)-1,3-butanedionate

[52] 398.09 6.4 Test

698 1,3-Bispiperidinepropanium di(1,1,1,5,5,5-hexafluoro-2,4-pentanedionate) [52] 343.08 15.1 Training699 Methyl-N-(2-methoxyethyl)piperidinium trifluoromethyltrifluoroborate [86] 299.43 16.4 Training700 Methyl-N-(2-methoxyethyl)piperidinium pentafluoroethyltrifluoroborate [86] 294.53 14.1 Training701 Methyl-N-(2-methoxyethyl)piperidinium


702 Methyl-N-(2-methoxyethyl)piperidinium (nonafluoro-n-butyl)trifluoroborate [86] 284.83 2.8 Training703 N-methyl-N-butyl-piperidinium trifluoromethyltrifluoroborate [86] 315.27 10.6 Training704 N-methyl-N-butyl-piperidinium pentafluoroethyltrifluoroborate [86] 310.37 1.2 Test705 N-methyl-N-butyl-piperidinium (heptafluoro-n-propyl)trifluoroborate [86] 305.51 13.7 Test

Please note that the references listed here are provided as the supplementary material (references for Table 2).

Fig. 3. Predicted melting temperature values of investigated ILS versus the experi-mental ones.

Fig. 4. Deviation of the estimated melting point values from the experimental ones.


Table 3Investigated classes of ionic liquids.

No Class AARD% Texpm range (K) Tpred

m range (K) N

1 1,3-Dialkyl imidazolium 7.1 196.55–454.15 214.26–435.07 2042 1-Alkyl imidazolium 6.9 250.15–389.15 253.77–351.24 153 Amino acids 6.9 248.15–459.15 280.58–398.86 254 Ammonium 7.5 216.15–490.95 223.71–477.52 1765 Double imidazolium 5.3 322.35–455.15 305.92–412.19 106 Guanidinium 9.0 279.15–367.15 298.63–371.97 127 Isoquinolinium 7.8 345.15–345.15 371.95–371.95 18 Morpholinium 8.8 274.15–433.55 287.83–378.75 199 Oxazolidinium 7.0 261.15–413.15 273.03–428.95 1310 Phosphonium 6.9 280.45–372.05 255.19–408.89 1811 Piperidinium 9.9 257.15–425.15 284.83–398.09 1412 Pyridazinium 0.8 259.15–259.15 261.13–261.13 113 Pyridinium 6.1 271–438.15 264.47–405.04 5214 Pyrrolidinium 9.2 255.15–393.15 285.63–355.10 2415 Pyrroline 5.1 292.15–384.15 316.06–370.09 516 Quinary alkyl imidazolium 4.1 391.15–486.15 397.41–450.94 317 Sulfonium 7.8 239.15–317.65 243.90–296.99 818 Tetra-alkyl imidazolium 8.3 338.15–434.15 332.15–370.20 219 Tetrazolium 8.4 324.15–406.15 370.75–407.80 320 Thiazolium 13.5 315.15–410.15 338.97–366.17 321 Tri-alkyl imidazolium 8.0 258.95–467.15 288.15–419.92 3322 Triazolium 6.5 218.35–446.15 246.36–429.01 6223 Uronium 7.7 273.15–305.15 277.95–290.63 2

np

simremombd

mpbsTbTtm

5

tmauttoctaInm

[

[

[

[

[[[[[

[[[[

[[[

umber of ILs in their data set is rather small, their accuracy ofrediction in terms of R2 and ARD% is higher than our study (Fig. 4).

The latest model proposed by Lazzús [19] worth considerationince the author employed the diverse data set of ionic liquids (400onic liquids). His proposed model is superior than the present

odel in term of R2. GC based models usually achieved betteresults than QSPR owing to the higher number of variables. How-ver, in term of AAD%, the accuracy of prediction of the presentodel is superior to Lazzús’ model. Since the present model is based

n the larger data set (nearly twice of the Lazzús data set) as well asore diverse array of anions and cations, its applicability domain is

roader than Lazzús model. By employing the broader applicabilityomain, the more reliable model can be achieved.

Table 3 explores the deviation of predicted values from experi-ental ones in classes of studied ionic liquids. The highest error of

rediction associated with Isoquinolinium group with one mem-er. Since only one ionic liquid from this family present in thistudy, the model cannot predict the acceptable value for this one.he predictions of melting points of other groups with more mem-ers are acceptable and lie in the range of experimental accuracy.he exclusive list of ionic liquids allocated with calculated descrip-ors, hat values and the references is provided as supplementary

aterial.

. Conclusion

In this study, a QSPR model is presented for prediction ofhe melting point of diverse classes of ionic liquids. The QSPR

odel is developed based on the most comprehensive sets ofnions and cations presented in the structure of 705 ionic liq-ids. The proposed model is a multivariate linear one consistingwelve variables (molecular descriptors). The molecular descrip-ors were selected using GFA technique and are calculated basedn the optimized structures of anions and cations. Also, Appli-ability Domain of the model is investigated and it turns outhat all investigated ILs are fall in this domain. In other word,
ll predictions conducted in the AD and therefore are reliable.n addition, analyzing the model with various validation tech-iques verify the reliability, robustness and stability of the presentodel.
[[

[

Appendix A. Supplementary data

Supplementary data associated with this article can be found, inthe online version, at http://dx.doi.org/10.1016/j.tca.2012.09.011.

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ionic liquids: prediction of melting point by molecular-based model

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