o.v. naumenko et al- intracavity laser absorption spectroscopy of hdo between 12145 and 13160 cm^-1

8/3/2019 O.V. Naumenko et al- Intracavity laser absorption spectroscopy of HDO between 12145 and 13160 cm^-1

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Intracavity laser absorption spectroscopyof HDO between 12145 and 13160 cm1

O.V. Naumenko a, B.A. Voronin a, F. Mazzotti b, J. Tennyson c, A. Campargue b,*

a Institute of Atmospheric Optics, Russian Academy of Sciences, Siberian Branch, Akademicheskii av.1, Tomsk 634055, RussiabLaboratoire de Spectrometrie Physique (associated with CNRS, UMR 5588), Universite Joseph Fourier de Grenoble,

B.P. 87, 38402 Saint-Martin-dHeres Cedex, Francec University College London, London WC1E 6BT, UK

Received 21 November 2007Available online 23 December 2007

Abstract

The high resolution absorption spectrum of monodeuterated water, HDO, has been recorded by Intracavity Laser Absorption Spec-troscopy (ICLAS) in the 1214513 160 cm1 region. The achieved sensitivity (noise equivalent absorption on the order ofamin$ 10

9 cm1) allowed detecting transitions with line strengths as weak as 1027 cm/molecule which is about 50 times lower thanthe weakest line intensities previously detected in the considered region.

The rovibrational assignment of the 1179 lines attributed to the HDO isotopologue was based on the results of the variational cal-culations of Schwenke and Partridge as well as the recent calculations based on a new HDO potential energy surface refined from thefitting to the available experimental data. The overall agreement between these new calculations and the observed spectrum is very good,the rms deviation of the differences between the calculated and observed energy values being 0.05 cm1. A set of 304 new experimentalHDO energy levels was obtained. In particular, band origins for the (1 2 2), (20 2), and (31 1) vibrational states, at 12 568.190, 12 644.652,

and 12919.938 cm1, respectively, and their rotational sublevels are derived for the first time. A detailed HDO database of 1337 tran-sitions was constructed and is provided as Supplementary Material. 2007 Elsevier Inc. All rights reserved.

Keywords: Water; Monodeuterated water; HDO; Rovibrational spectroscopy; Intracavity Laser Absorption Spectroscopy (ICLAS)

1. Introduction

This work is part of our study of the absorption spec-trum of HDO by Intracavity Laser Absorption Spectros-copy (ICLAS) with a Ti: Sapphire laser. In a first report,

we analyzed the 1164512330 cm1

region dominated bythe m2 + 3m3 band at 11969.76 cm1 [1]. The presently

investigated 1214513 160 cm1 region corresponds toweaker bands and extends to high energy our previousstudy. An overview of the spectrum as predicted bySchwenke and Partridge (SP) [4,5] in the 1165013600 cm1 region is presented in Fig. 1. Previous experi-

mental investigations of HDO up to the visible region havebeen reviewed in Refs. [13]. The wide 11 50023000 cm1

region has been recently studied by Fourier TransformSpectroscopy (FTS) associated with a 600 m path length[3,6]. Absolute line intensities and pressure shifts were

obtained but in our region of interest, the sensitivity wasnot optimum (the detectivity threshold was about5 1026 cm/molecule for pure HDO). Another FTS spec-trum, previously obtained in the 1011012215 cm1 with a105 m absorption path length [8], has a similar sensitivityto that of Refs. [3,6]. This spectrum [8] does not show tran-sitions in our region except the strongest lines in the narrow1214512 214 cm1 spectral section. The region of theDvOD = 5m1 stretching overtone corresponding to the 5v1band centered at 12767.13 cm1, was also investigated byICLAS associated with a FTS detection scheme [9]. Two

0022-2852/$ - see front matter 2007 Elsevier Inc. All rights reserved.

doi:10.1016/j.jms.2007.12.005

* Corresponding author. Fax: +33 4 76 63 54 95.E-mail address: [email protected] (A. Campargue).

www.elsevier.com/locate/jms

Available online at www.sciencedirect.com

Journal of Molecular Spectroscopy 248 (2008) 122133
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hundred and seventy-five lines were assigned in the 1255012900 cm1 region but the sensitivity was again similar tothat of the recent FTS study [6]. For completeness, we men-tion the detection and assignment of about 120 transitionsof the same 5v1 band in the 1272012911 cm

1 by photoa-coustic spectroscopy [10]. Compared to these four above

studies, our increased sensitivity allows lowering the detec-tion limit by at least a factor of 50, resulting in the detec-tion of many new lines with intensities down to1027 cm/molecule. Finally, our investigation of the1316513 500 cm1 region by ICLAS with a dye laser [7]should be mentioned as some of the reported energy levelsare upper levels of transitions lying in the presently investi-gated region.

2. Experimental details

The spectra were recorded with the ICLAS spectrometerbased on a Ti: Sapphire laser as described in Refs. [1,1113]. The only significant change is that a new intracavityabsorption cell was designed and inserted in the Ti:Sa lasercavity in order to increase its occupation ratio. The lengthof the new cell is 65 cm which allowed increasing the fillingratio from 32% to 42%. The spectra were recorded with ageneration time of 190 ls corresponding to an equivalentabsorption path length of about 24 km. The intracavitysample cell was filled with a 1:1 mixture of H2O and D2Oat a typical pressure of 18.4 hPa. A H2O:HDO:D2O mix-ture in a proportion of about 1:2:1 was then obtained.The spectral resolution fixed by the grating spectrographwas close to the Doppler line broadening. The 12145

13160 cm1

region was covered by a total of 105 spectral

snapshots overlapping by about 4 cm1 on each side. Addi-tional recordings were performed at lower pressures in thespectral regions corresponding to the stronger transitions,so as to obtain well resolved lines.

Atmospheric absorption due to water and oxygen pres-ent in the laser cavity partly obscures the HDO spectrum in

the investigated region. In particular, the A band of molec-ular oxygen lying between 12900 and 13160 cm1 makesdifficult the recording of the HDO spectrum in this region.It was then necessary to drastically reduce the contributionof the intracavity air by placing the Ti:Sa laser in a boxwhere dry nitrogen was continuously flown. After a fewminutes, atmospheric absorption was decreased by abouttwo orders of magnitude. The residual absorption was fur-ther efficiently suppressed by filling the cell with deuteratedwater, recording the spectrum, vacuuming the cell andrecording the background spectrum. This procedure hasthe additional advantage of increasing the signal to noiseratio as the fringes frequently appearing on the spectrumbaseline are stable over the time scale of the full operation(about 30 s) and can then be efficiently suppressed.

Each 12 cm1 wide portion of the spectrum wasrecorded with a 3754 diodes silicon array and calibratedindependently using reference line positions. As a rule,the H2

16O and HDO reference lines provided in the data-base attached to Ref. [14] and Refs. [3,6], respectively, wereadopted as references except in the 1280013 160 cm1

region where these line lists are too sparse and sometimesnot reliable. By chance, this spectral region includes transi-tions of the oxygen A band which is observed between12900 and 13160 cm1 as a consequence of the residual

intracavity oxygen. The O2 line positions were then used

Fig. 1. Overview of the HDO spectrum in the 1165013600 cm1 region as predicted by Schwenke and Partridge [4,5]. The spectral regions previouslyinvestigated by ICLAS are indicated.

O.V. Naumenko et al. / Journal of Molecular Spectroscopy 248 (2008) 122133 123


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for wavenumber calibration purpose. We adopted thewavenumber values as provided by the HITRAN database[15] and applied a constant pressure shift of0.009 cm1

as measured in Ref. [16]. The wavenumber calibration ofthe 1280012900 cm1 region was more problematic: wehad to combine some reliable FTS line positions [3,14] with

line positions calculated from well known energy levels inorder to build a sufficient set of reference lines. The lackof precise reference lines may have led to errors up to0.010 cm1 in some very limited cases but we estimate thatthe accuracy of the wavenumber calibration is on the orderof 0.004 cm1 as will be confirmed below by the uncer-tainty obtained for the energy levels retrieved from severaltransitions.

The line positions and relative line intensities were thendetermined by using an interactive least squares multi-lines

fitting program assuming a Voigt profile for each line. Lineposition, integrated line absorbance, Gaussian andLorentzian widths of each line and the corresponding base-line (assumed to be a linear function of the wavenumber)were derived from the multiline fitting procedure.

The determination of absolute line intensity values

requires the knowledge of the HDO partial pressure andof the absorption path length. As in our experiment, thegeneration time is controlled, the absorption path lengthis known but an accurate determination of the HDO con-centration is more problematic. Indeed, a drawback ofthe experimental procedure consisting in successively fillingand emptying the cell with deuterated water, is that theH2O:HDO:D2O proportion may change from one record-ing to the next. As a consequence of the rapid protonexchange between the gas phase and water adsorbed on

Fig. 2. Overview comparison of the HDO spectrum in the 12145-13160 cm1 region. (a) Calculations of Schwenke and Partridge [4,5], (b) ICLAS (thiswork), (c) FTS spectrum of Refs. [3,6]. Note the logarithmic scale used for the line intensity values. In (a), the SP intensity values were not summed in the

case of unresolved multiplets. This is why a few ICLAS intensity values appear to exceed significantly SP values in the case of blended lines.

124 O.V. Naumenko et al. / Journal of Molecular Spectroscopy 248 (2008) 122133


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the wall of the cell, the HDO concentration was observedto evolve with time and consequently from an elementaryspectrum to the next one. The situation was even morecomplicated as the total pressure value itself may decreaseduring the recording of an individual spectrum, as a resultof the adsorption on the cell wall. We then found more

consistent and accurate to normalize the relative intensityvalues retrieved from each elementary spectrum, againstthe intensity values calculated by Schwenke and Partridge[5]. Such normalization is justified by the good agreementobserved up to the visible range between SP intensitiesand the FTS intensity values of Refs. [3,6].

The most complete line list was obtained by gatheringthe line lists associated with individual spectra. As several

recordings of the same spectral window were often per-formed and because of overlapping regions, many linesappear several times in this list. The accuracy of the ICLASline positions being estimated to be around 0.004 cm1, weconsidered as identical two lines when both the differenceof their positions was less than 0.008 cm1 and their inten-

sities differed by at most a factor of 2. The position andintensities of these identical lines were averaged leadingto a global line list which was further checked and cleanedfrom spurious lines or irreproducible spectral features closeto the noise level. The obtained list was then considered forthe rovibrational analysis. Fig. 2 illustrates the increasedsensitivity compared to previous measurements [3,6] andthe good agreement with SP calculations in the overall

12835 12840

0

8x10-26

0.0

0.4

0.8

0

8x10-26

0

8x10-26

Wavenumber (cm-1)

FTS

N

apierian

ab

sorbance

ICLAS

Linestrength

(cm/molecule

)

VTT

Linestrength(cm/molecule)

SP

a

b

c

d

Fig. 3. The spectrum of HDO in the region of the head of the 5m1 band near 12840 cm1: (a) VTT predictions of Refs. [23,24]. (b) ICLAS spectrum of

deuterated water recorded at a total pressure of about 18 hPa with an equivalent absorption pathlength of 24 km. In the considered interval, thecontribution of H2O is negligible while D2O contribution is very limited. (c) Variational calculations of Schwenke and Partridge [4,5], (d) FTS

measurement of Refs. [3,6].



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region. Similar comparison limited to a small spectral sec-tion is presented in Fig. 3.

3. Spectral analysis

3.1. Spectrum assignment and energy levels derivation

The experimental line list contained altogether about2500 absorption lines which resulted from the H2O, HDOand D2O contributions. The H2O contribution is strong inthe low energy part of the studied spectrum and becomesmuch weaker above 12 700 cm1. The D2O absorption linesare relatively strong in the region of the DvOD = 5 bandaround 12700 cm1 and are observed with weaker intensi-

ties up to 13160 cm1. The discrimination of the HDO lineswas greatly helped by the comparison with the H2O andD2O ICLAS spectra that we recorded separately. Asreported in Refs. [17,18], we recently obtained a D2O ICLASspectrum with enrichment close to 100% while the knowl-edge of the H2O spectrum was also improved by our ICLAS

measurements in the same region [19,20]. Fig. 4 shows thecomparison of the ICLAS spectra in a small spectral sectionaround 12800 cm1 where the absorption lines of D2O,HDO and H2O are on the same order of magnitude. Finally,after identification of the H2O a n d D2O lines, 1185 lines pre-sumably due to HDO were left.

In the most recent HDO studies, the line assignment wasbased on the comparison with SP predictions [4,5]. These

12718 12720 12722

0.0

0.5

1.0

0.0

0.5

1.0

0.0

0.5

1.0

Wavenumber (cm-1)

D2O

H2O

Transmittance

D2O:HDO:H2O

Fig. 4. ICLAS spectrum of H2O (upper panel), D2O (lower panel) compared to the ICLAS spectrum of deuterated water (medium panel) showing thesuperposition of H2O, HDO and D2O lines. In the considered spectral interval, transitions of the three water isotopologues have comparable intensities.

Such comparison is very useful to discriminate the HDO lines.



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calculations were found accurate enough for the assign-ment of the FTS spectrum of Ref. [3], in the wide spectralrange from 11600 to 26000 cm1. However, compared toRef. [3], our increased sensitivity leads to a much higherdensity of observed transitions. Compared to the averageseparation of the weak lines, the accuracy of SP calcula-

tions was not sufficient to base our assignments only onthe agreement between the observed and calculated linepositions. Since the publication of SP results in 1997, manynew HDO levels have been determined. A new HDO PES[21] was recently optimized through the fitting to the avail-able HDO energy levels with J6 8. A standard deviationof 0.035 cm1 was obtained for the residuals between theobserved and calculated values of 4495 experimentalenergy levels of more than 90 vibrational states. ThisPES has been used by some of us with a new, ab initiodipole moment surface [22] to compute a comprehensivelinelist for HDO, which we refer to as VTT (Voronin, Tol-chenov, Tennyson) below. Preliminary results for the VTT

linelist have already been given [23] and the full linelist,which is still under construction, will be published else-where [24]. As detailed below, a synthetic spectrumobtained from the VTT linelist was used in the assignmentprocess.

As a result of the spectral analysis, 1179 observed HDOlines could be assigned. This number should be comparedto the 293 HDO lines detected by FTS in the same spectralregion [3,6] (see Fig. 2). Only six lines among the weakestwere left unidentified. The line list attached to this paperas Supplementary Material presents the observed HDOwavenumbers followed by the observed and calculated

(SP) intensities and rovibrational assignments. As a conse-quence of double and triple assignments of some lines, itcorresponds to 1337 transitions. A number of HDO transi-tions which are superimposed on the H2

16O (25 lines),H2

18O (4) or D2O (51) transitions, as well as lines with ten-tative assignment are specifically indicated.

Table 1 summarizes the obtained spectroscopic informa-tion: 592 rovibrational energy levels belonging to 15 vibra-tional states were derived, 304 of them being newlydetermined. New information concerns, mainly, the highJand K

aenergy levels of the previously studied (500) state

[3,9,10] and three newly observed vibrational states: (202),(122), and (311) at 12568.190, 12644.652, and12919.938 cm1, respectively. The newly observed HDOenergy levels are listed in Tables 2 and 3 while the completeset is attached to this paper as Supplementary Material.Energy levels derived from blended lines and consequently,with less accuracy, are marked. The tables also includedeviations of the experimental values from VTT predic-tions [24] and the statistical experimental uncertainty forthe levels determined from several transitions.

The improved quality of the new HDO VTT linelist isillustrated in Fig. 5, where the (obs. calc.) deviations ofthe studied energy levels are plotted versus J+ K

a/J for

both SP and VTT predictions. The most important VTT

and SP deviations are 0.16 and 0.64 cm1

, respectively.

A selected part of the ICLAS spectrum in the region ofthe head of the 5m1 band is shown in Fig. 3 along withthe FTS stick spectrum [3,6], VTT and SP predictions.The significant shift of SP line positions with respect tothe experimental spectrum is clear, while VTT line centrescoincide very well with the observed spectrum. The rootmean square value of the differences between observedand VTT energy levels is only 0.05 cm1. In general, the

observed rotational dependence of the (obs. calc.) devia-tions is less pronounced for VTT predictions compared toSP data. For instance, in the case of the (500) state, SPdeviations range from 0.06 to 0.64 cm1, while VTT devi-ations vary from 0.16 to 0.11 cm1.

Along with the accurate predicted HDO line positions, areasonable match between the experimental and calculatedintensities proved to be a key criterion in the assignmentprocedure, in particular for the weak lines not includedinto ground state combination difference (GSCD) rela-tions. Fig. 6 shows the observed-to-SP calculated intensityratio for the assigned HDO lines. The overall agreement

between theory and experiment is quite satisfactory andsufficient to support our line assignments. As only separateSP predicted intensities were used for the scaling of theexperimental line intensities, the agreement observed forthe whole set of observed lines is then significant.

4. Discussion

The HDO molecule is known to undergo strong centrif-ugal distortion effects leading to strong high-order reso-nance interactions involving highly exciting bendingstates. In this study, a number of transitions reaching high

bending states like (151), (061), (071) and (180) were

Table 1Summary of the experimental observations retrieved for HDO from theanalysis of the ICLAS spectrum between 12145 and 13160 cm1

v1v2v3 Band origins (cm1) N levels

Observed Calc. (VTT) Calc. (SP) Totala New

0 6 1 11 533.35 11 533.48 3 0

1 4 1 11 804.55 11 804.57 3 03 3 0 11 958.56b 11 958.60 11 958.26 1 00 1 3 11 969.7530 11 969.75 11 970.07 84 4

0 10 0 12 164.85 12 165.80 1 10 4 2 12 516.42 12 516.63 10 102 0 2 12 568.1901 12 568.15 12 568.19 77 771 2 2 12 644.6528 12 644.65 12 644.72 72 720 7 1 12 694.33 12 694.53 2 25 0 0 12 767.1355 12 767.16 12 766.72 120 351 8 0 12 852.35 12 852.95 2 23 1 1 12 919.9387 12 920.04 12 919.95 76 761 5 1 12 986.79 12 986.67 1 10 2 3 13 278.3508 13 278.34 13 278.44 77 101 0 3 13 331.6061 13 331.59 13 331.74 63 14

Total 592 304a Total number of known energy levels including those available in the

literature and those presently determined.b Extrapolated value from Ref [1].

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6 5 2 D 13 212.3256 1 0.02 13 627.9306 1 0.09 D 13435.89806 5 1 D 13 212.3128 1 0.00 13 627.9294 1 0.09 D 13435.88186 6 1 13 354.8444 1 0.016 6 0 13 354.8444 1 0.017 0 7 12 949.7228 1.1 3 0.00 13 298.6916 1.7 2 0.08 13034.36397 1 7 12 950.7139 1.4 3 0.00 13 296.3146 2.5 3 0.10 13035.57397 1 6 D 13 022.2065 1 0.04 13 371.4857 0.1 2 0.11 13117.83707 2 6 13 025.2328 2.6 3 0.00 13 390.7219 1 0.10 13 136.11217 2 5 13 057.1011 1 0.02 13 421.0299 1 0.11 13173.97787 3 5 13 105.4838 1 0.00 13 481.0961 1 0.09 13 239.9679

7 3 4 13 485.7740 1

0.12 13 245.49007 4 4 13 198.9595 5.1 2 0.01 13 591.7501 5.5 2 0.13 13372.42417 4 3 13 199.3912 4.8 2 0.00 13 591.7832 1 0.11 13 370.61407 5 3 T 13 730.3507 1 0.117 5 2 T 13 730.3519 1 0.12 13 545.33317 6 2 13 458.2027 1 0.007 6 1 13 458.2015 1 0.008 0 8 13 052.9964 1.2 3 0.00 13 400.6352 0.5 2 0.07 13139.64528 1 8 13 053.5357 3.5 3 0.00 13 397.6941 3.9 3 0.09 13138.81238 1 7 13 489.4659 1 0.11 13 240.43978 2 7 13 138.1229 1.9 2 0.03 13 503.7508 0.2 2 0.09 13253.51868 2 6 13 184.9471 1 0.02 13 547.2156 1 0.108 3 6 13 224.4107 2.6 2 0.01 13 598.7292 1 0.098 3 5 13 236.8667 1 0.00 13 608.5013 1 0.12 13 375.20488 4 5 13 318.6100 1 0.01 13 497.7505

8 4 4 13 710.3215 1 0.119 0 9 13 168.1509 3.4 2 0.02 13 515.7159 1 0.06 13252.43989 1 9 13 168.4517 6.9 3 0.01 13 254.72019 1 8 D 13 259.1045 1 0.04 13 619.0550 1 0.11 13374.81669 2 8 13 629.8525 1 0.09 D 13 383.54529 2 7 13 326.8329 1 0.03 13 454.69719 3 7 13 357.3877 1 0.03 13 730.2059 1 0.119 3 6 13 378.9099 1 0.059 4 6 13 453.3079 1 0.03 13 842.7323 1 0.12 13639.7909

10 0 10 13 295.1141 5.2 2 0.09 13 631.4918 1 0.1010 1 10 13 295.3372 4.8 2 0.07 D 13 635.3844 1 0.09 13382.5139

10 1 9 13 759.9434 1 0.12 D 13 520.712410 2 9 13 403.9385 1 0.09 13 762.0209 1 0.12

11 0 11 13 434.2157 1 0.09 T 13 770.2200 1 0.12 13521.922212 0 12 13 673.7046

This list is limited to the newly derived energy levels, the complete set of the rotational levels of the considered states being included in the Supplemexperimental determinations.

Note. Nis the number of lines used for the upper energy level determination and r denotes the corresponding experimental uncertainty. D is the difference beVTT predictions of Refs. [23,24]. D denotes the energy level derived from distorted line and then with less accuracy. Energy levels marked with T were derivtext).
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highly excited bending states. Fig. 7 shows the Obs./Calc.ratio for the transitions observed in this work or in our pre-

vious study [1], which borrow their intensity from reso-nance partners. A much better agreement is noted for theVTT calculated intensities while SP intensity values maydeviate from the experimental data by as much as a factor200. A Table placed in the Supplementary Material, liststhe considered transitions together with the quantitativecomparison of their observed and calculated intensities.

As mentioned above, the whole or parts of the spec-tral region considered in this study, were previously stud-ied [1,3,710]. In the table of the energy levels attachedas Supplementary Material, the previous determinationsof the energy levels of the (013), (023), (103) and

(050) states are included and compared with our values.

Good agreement is obtained with the values reported inthe recent works [1,3], with rms deviation from our val-

ues of 0.006 cm1. Significant deviations with the resultsof Refs. [7,9] are noted for the (023), (103) and (500)states. A calibration problem was already pointed inRef. [3]: compared to our values, the (103) and (023)energy levels of Ref. [7] are higher by 0.006 cm1 onaverage, while the rms deviation from our data is0.013 cm1. The (500) energy levels of Ref. [9], on thecontrary, are underestimated by 0.011 cm1 on averagecompared to our data with a rms deviation of0.015 cm1. We also noticed a small negative shift of0.003 cm1 on average between our values for the(013) state and those of Ref. [8], the rms deviation being

about 0.011 cm1

.

0 12 16

-0.8

-0.4

0.0

0.4

0.8

Eobs-Ecalc

b

Eobs-Ecalc

J+Ka/J

0 4

4

8

8

12 16

-0.8

-0.4

0.0

0.4

0.8

a

Fig. 5. Differences (in cm1) between the observed and calculated values for the HDO energy levels determined from the ICLAS spectrum between 12 140and 13160 cm1. (a) Variational calculations of Schwenke and Partridge [4,5], (b) VTT predictions of Refs. [23,24].

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The energy levels set for the (500) state was signifi-cantly enlarged in this study (120 levels), and we recom-

mend the present set as the most accurate and complete.

Compared to our previous studies [1,3,8], only fourenergy levels were newly determined for the (013) state,

the most complete set relative to this state can be found

1E-27 1E-26 1E-25

0

1

2

3

Intensityratio:ICLAS/SP

ICLAS/SP

SP line intensity (cm/molecule)

Fig. 6. Ratio of the ICLAS line intensities by the intensity values calculated by Schwenke and Partridge [5]. Note that a number of HDO lines from theresulting linelist was excluded from the comparison in case when they were superimposed to H 2O or D2O lines.

Iobs

obs

/ISP

I /IVTT

12000 12200 12400 12600 12800

Energy level (cm-1)

0.1

1

10

100

Iobs/Icalc

Fig. 7. Variation of the observed to calculated line intensities versus the wavenumber for selected transitions borrowing their intensity from a resonancepartner. The considered transitions with their corresponding intensities are listed in a Table provided as Supplementary Material. The ratio valuesobtained from VTT (Refs. [23,24]) and SP [4,5] calculations are plotted with a different symbol.



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in Ref. [1] where 179 levels were reported (instead of 84presently observed).

In the case of the (103) and (023) states, 196 energy lev-els were determined in our previous ICLAS study in the1310013 500 cm1 region [7]. As discussed above, thesevalues are slightly shifted due to a calibration problem.

In the present study, 140 energy levels were determinedfor the (103) and (023) set, 24 of them being new. Asthe center of the m1 + 3m3 and 2m2 + 3m3 bands are situatedwell above the investigated region, we observed mostlyweak P-branch transitions that resulted in the absence ofGSCD and in a certain decrease of accuracy of the energylevels values. The values attached to Ref. [3] (174 energylevels) may be considered as the most accurate for the(103) and (023) when supported by GSCD relations; how-ever, energy levels derived in [3] from single weak lines maybe equally (sometimes even less) accurate than our presentresults. Thus, the optimal energy levels set for the (103)and (023) states may be obtained by combining the set

of Ref. [3] completed with our new observations, with cor-rected levels from Ref. [7]. We did not attempt to recali-brate our previous data of Ref. [7], as we have recentlyrecorded with a higher sensitivity the HDO spectrum inthe 1316014 000 cm1 region. The future analysis of thisnew ICLAS spectrum will improve and replace our previ-ous results [7] and will lead to the most complete datasetfor the (103) and (023) states.

5. Conclusion

The high resolution rovibrational spectrum of the

HDO molecule has been recorded by ICLAS in the wide1214013 160 cm1 region. The assignment of the 1179HDO lines was performed on the basis of an improvedHDO PES [21]. Five hundred and ninety-two accurateenergy levels belonging to fifteen vibrational states werederived, 304 of them being newly determined. Transitionsreaching the (12 2), (20 2), and (31 1) vibrational stateswere observed for the first time. The HDO line list pro-vided in the Supplementary Material may be consideredas the most complete database in the analyzed region.VTT calculations [23,24] were found to improve signifi-cantly SP calculations: (i) on average VTT energy levelsvalues deviate by only 0.05 cm1 from our experimentalvalues, (ii) in the case of strongly perturbed transitionsreaching energy levels in strong resonance, the observedline intensities are much better reproduced by VTT calcu-lations than by SP results.

Acknowledgments

This work is supported by a collaborative project be-tween CNRS and RFBR (PICS Grant No. 05-05-22001).This study was performed as part of IUPAC Task Group2004-035-1-100) to compile, determine, and validate, bothexperimentally and theoretically, a database of water tran-

sitions. A. Campargue is grateful for the financial support

provided by the Programme National LEFE (CHAT) ofCNRS (INSU). This work was performed as part theQUASAAR Marie Curie Training Network.

Appendix A. Supplementary data

Supplementary data associated with this article can befound, in the online version, at doi:10.1016/j.jms.2007.12.005.

References

[1] A. Campargue, I. Vasilenko, O. Naumenko, J. Mol. Spectrosc. 234(2005) 216227.

[2] E. Bertseva, O. Naumenko, A. Campargue, J. Mol. Spectrosc. 221(2003) 3846.

[3] B.A. Voronin, O.V. Naumenko, M. Carleer, P.-F. Coheur, S. Fally,A. Jenouvrier, R.N. Tolchenov, A.C. Vandaele, J. Tennyson, J. Mol.Spectrosc. 244 (2007) 87101.

[4] H. Partridge, D.W. Schwenke, J. Chem. Phys. 106 (1997) 46184639.[5] D.W. Schwenke, H. Partridge, J. Chem. Phys. 113 (2000) 65926597.[6] M. Bach, S. Fally, P.-F. Coheur, M. Carleer, A. Jenouvrier, A.C.

Vandaele, J. Mol. Spectrosc. 232 (2005) 329338.[7] O. Naumenko, E. Bertseva, A. Campargue, D. Schwenke, J. Mol.

Spectrosc. 201 (2000) 297309.[8] O. Naumenko, S. M. Hu, S. G. He, A. Campargue, Phys. Chem.

Chem. Phys. 6 (2004) 910918.[9] S. Hu, H. Lin, S. He, J. Cheng, Q. Zhu, Phys. Chem. Chem. Phys. 1

(1999) 37273730.[10] V.V. Lazarev, T.M. Petrova, L.N. Sinitsa, Q.-S. Zhu, J.-X. Han, L.-

Y. Hao, Atmos. Oceanic Opt. 11 (1998) 809812.[11] A. Campargue, M. Chenevier, F. Stoeckel, Spectrochim. Acta Rev. 13

(1990) 6988.[12] A. Kachanov, A. Charvat, F. Stoeckel, J. Opt. Soc. Am. B 11 (1994)

24122419.[13] M. Herman, J. Lievin, J. Vander Auwera, A. Campargue, Adv.

Chem. Phys. 108 (1999) 1431.[14] R.N. Tolchenov, J. Tennyson, J.W. Brault, A.A.D. Canas, R.

Shermaul, J. Mol. Spectrosc. 215 (2002) 269274.[15] L.S. Rothman, D. Jacquemart, A. Barbe, D. Chris Benner, M. Birk,

L.R. Brown, M.R. Carleer, C. Chackerian Jr., K. Chance, V. Dana,V.M. Devi, J.-M. Flaud, R.R. Gamache, A. Goldman, J.-M.Hartmann, K.W. Jucks, A.G. Maki, J.Y. Mandin, S.T. Massie, J.Orphal, A. Perrin, C.P. Rinsland, M.A.H. Smith, J. Tennyson, R.N.Tolchenov, R.A. Toth, J. Vander Auwera, P. Varanasi, G. Wagner, J.Quant. Spectrosc. Radiat. Transf. 96 (2005) 139204.

[16] C. Hill, D.A. Newnham, J.M. Brown, J. Mol. Spectrosc. 219 (2003)6569.

[17] O.V. Naumenko, F. Mazzotti, O. Leshchishina, J. Tennyson, A.Campargue, J. Mol. Spectrosc. 242 (2007) 19.

[18] A. Campargue, F. Mazzotti, S. Beguier, O.L. Polyansky, I. Vasilenko,O.V. Naumenko, J. Mol. Spectrosc. 245 (2007) 8999.

[19] F. Mazzotti, O.V. Naumenko, S. Kassi, A.D. Bykov, A. Campargue,J. Mol. Spectrosc. 239 (2006) 174181.

[20] A. Campargue, A.W. Liu, S.N. Mikhailenko, J. Mol. Spectrosc.,submitted for publication.

[21] S.N. Yurchenko, B.A. Voronin, R.N. Tolchenov, N. Doss, O.V.Naumenko, W. Thiel, J. Tennyson, J. Chem. Phys., in press.

[22] L. Lodi, R.N. Tolchenov, J. Tennyson, A. E. Lynas-Gray, S.V.Shirin, N.F. Zobov, O.L. Polyansky, A.G. Csaszar, J. van Stralen, L.Visscher, J. Chem. Phys., in press.

[23] J. Tennyson, G.J. Harris, R.J. Barber, S. La Delfa, B.A. Voronin,Y.V. Pavlenko, Mol. Phys. 105 (2007) 701714.

[24] B.A. Voronin, R.N. Tolchenov, J. Tennyson, submitted for

publication.

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o.v. naumenko et al- intracavity laser absorption spectroscopy of hdo between 12145 and 13160 cm^-1

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