relative permittivities and refractive indices of binary mixtures of cyclohexanone with...
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Ž .Fluid Phase Equilibria 145 1998 89–97
Relative permittivities and refractive indices of binary mixtures ofcyclohexanone with dichloromethane, trichloromethane,
1,2-dichloroethane, trichloroethene and cyclohexane at Ts303.15 K
Jagan Nath ) , Sanjay Kumar Mishra
Chemistry Department, Gorakhpur UniÕersity, Gorakhpur 273009, India
Received 30 June 1997; accepted 1 October 1997
Abstract
Relative permittivities, e , and refractive indices, n , have been measured for binary liquid mixtures ofr DŽ . Ž . Ž .cyclohexanone C H O with dichloromethane CH Cl , trichloromethane CHCl , 1,2-dichloroethane6 10 2 2 3
Ž . Ž . Ž .CH ClCH Cl , trichloroethene CHClCCl , and cyclohexane c-C H at Ts303.15 K. The values of the2 2 2 6 12
deviations of e and n from values arising from mole fraction average, which are represented respectively byr D
De and Dn have been calculated. Values of e and Dn have been fitted by the method of least squares tor D r D
smoothing equations. De for the various mixtures has been discussed from the viewpoint of the existence ofr
specific interactions between the components. q 1998 Elsevier Science B.V.
Keywords: Relative permittivity; Refractive index; Cyclohexanone
1. Introduction
Ž . Ž .Binary mixtures of cyclohexanone C H O with dichloromethane CH Cl , trichloromethane6 10 2 2Ž . Ž . Ž . ŽCHCl , 1,2-dichloroethane CH ClCH Cl , trichloroethene CHClCCl , and cyclohexane c-3 2 2 2
.C H are of considerable interest from the viewpoint of the existence of an electron donor–acceptor6 12
interaction leading to the formation of intermolecular complexes between the components in the liquidstate. The specific interaction of C H O with CH Cl , CHCl , CH ClCH Cl, and CHClCCl can6 10 2 2 3 2 2 2
be thought of as being due to the presence of lone-pair electrons on the oxygen atom of C H O on6 10
account of which it can act as an n-donor towards these chloro-compounds which can be involved inthe formation of hydrogen bonds with, and act as s-acceptors toward C H O. The system6 10
C H Oqc-C H can be treated as a reference system since the non-specific forces are believed to6 10 6 12
) Corresponding author.
0378-3812r98r$19.00 q 1998 Elsevier Science B.V. All rights reserved.Ž .PII S0378-3812 97 00308-7
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–9790
w xbe present between the components in this case. Although Nath and Dixit 1,2 have mademeasurements of excess molar volumes, V E, ultrasonic velocities, u, relative permittivities, e , andm r
refractive indices, n , for mixtures of dimethylketone with CH Cl , CH ClCH Cl, CHClCCl , andD 2 2 2 2 2w x ECCl CCl , Nath and Saini 3,4 have measured V , u, e and n for mixtures of methylethylketone2 2 m r D
Ž .CH COC H with CH Cl , CH ClCH Cl, CHClCCl , and CCl CCl , and Chadha and Tripathi3 2 5 2 2 2 2 2 2 2w x E5 have measured excess molar enthalpies, H , for mixtures of CHCl CHCl with cyclopentanone,m 2 2
extensive studies concerning interactions between the components of mixtures of organic chloro-com-pounds with ketones of more complexity have not been made. Hence, we have measured relative
Ž .permittivities, e , and refractive indices, n , of cyclohexanone C H O qCH Cl , qCHCl ,r D 6 10 2 2 3
qCH ClCH Cl, qCHClCCl , and qc-C H , and the results of these measurements are reported2 2 2 6 12
and interpreted here.
2. Experimental
2.1. Materials
HPLC quality chemicals dichloromethane and 1,2-dichloroethane both of stated minimum purity ofŽ . Ž .99.8% GLC , and cyclohexane of stated minimum purity of 99.7% GLC , UV spectral grade
Ž .trichloroethene of minimum purity of 99.5% GLC , and AR quality cyclohexanone of statedŽ .minimum purity 99.5%, were all obtained from Sisco Research Laboratories, Mumbai India .
CH Cl , CH ClCH Cl, c-C H , and CHClCCl were used without further purification. Cyclohex-2 2 2 2 6 12 2
anone was placed over anhydrous sodium sulphate to remove traces of water, and then subjected toŽfractional distillations. Trichloromethane of AR quality obtained from Qualigens Fine Chemicals,
.Mumbai, India was shaken repeatedly with distilled water to remove ethanol present as stabilizer,dried over anhydrous calcium chloride, and then distilled fractionally. The densities of the various
Table 1Densities, r ), refractive indices, n), and relative permittivities, e ) of the pure component liquids at T s303.15 KD r
) y3 ) )Ž .Compound r g cm n eD r
This work Lit. This work Lit. This work Lit.a a cCH Cl 1.30774 1.30777 1.4184 1.4184 8.709 8.7042 2a a dCHCl 1.47058 1.47060 1.4396 1.43973 4.631 4.6313a a eCH ClCH Cl 1.23834 1.23831 1.4396 1.43955 10.072 10.0752 2
a a eCHClCCl 1.45143 1.4514 1.4716 1.4718 3.335 3.3402ab ec-C H 0.76922 0.76918 1.4206 1.42083 2.008 2.00706 12
a a fC H O 0.93758 0.93761 1.4498 1.44885 17.950 18.16 10
a w xRiddick and Bunger 6 .b w xWood and Gray 7 .c w xNath and Chaudhary 8 .d w xNath and Dubey 9 .e w xNath and Dixit 2 .f w x )The literature 10 value 18.1 of e for cyclohexanone is at T s298.15 K.r
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–97 91
pure liquids measured at Ts303.15 K with an uncertainty of the order of "2=10y5 g cmy3, usinga single-capillary pycnometer, are given in Table 1.
2.2. Methods
Ž . Ž .i Relative permittivities, e , were measured at 303.15"0.01 K and at 1.8 MHz with arŽ .dekameter type DK Wissenschaftlich–Technische, Werkstatten, Germany , using one cell MFL¨03
1rS, no. 2078, for mixtures having e -7.0, and another cell MFL 2rS, no. 2084, for mixturesrŽw x.having e )7.0, as described earlier 11,8 . The imprecision in e is ;0.002 units for mixturesr r
having e -7.0, and ;0.005 units for mixtures having e )7.0.r rŽ . Ž . Ž .ii The refractive indices sodium D line , n , were measured at 303.15"0.01 K, with anD
accuracy of "0.0002, using a thermostated Abbe refractometer.
3. Results and discussion
The values of the refractive indices, n), and the relative permittivities, e ), of the pure liquidsD r
CH Cl , CHCl , CH ClCH Cl, CHClCCl , c-C H , and C H O, at Ts303.15 K are given in2 2 3 2 2 2 6 12 6 10
Table 1, whereas the values of e of the mixtures of C H O with CH Cl , CHCl , CH ClCH Cl,r 6 10 2 2 3 2 2
CHClCCl , and c-C H at Ts303.15 K are given in Table 2, and the values of n for these2 6 12 D
mixtures at Ts303.15 K are given in Table 3, where x refers to the mole fraction of C H O. The6 10
values of x have the uncertainty of "0.0001. The values of e for the various mixtures have beenr
fitted by the method of least squares to the equationn
jy1e s A x 1Ž .Ýr jjs1
Ž . Ž .The values of the parameters A of Eq. 1 , along with the standard deviations d e for the variousj r
systems are listed in Table 4.The values of the changes of refractive index on mixing, Dn , for the various mixtures of C H OD 6 10
were calculated from the refractive indices n of the mixtures, using the relationD
Dn sn yÝ x n) 2Ž .D D i D , i
where n) refers to the refractive index of the pure component i and x is the mole fraction of theD,i i
component i in the mixture.w xIglesias et al. 12 have also represented the refractive index data for mixtures, by Dn . The valuesD
Ž . Ž . Žof Dn for x C H O q 1 y x CH Cl , x C H O q 1 y x CHCl , x C H O q 1 yD 6 10 2 2 6 10 3 6 10. Ž . Ž .x CH ClCH Cl, x C H Oq 1yx CHClCCl , and x C H Oq 1yx c-C H , have been plot-2 2 6 10 2 6 10 6 12
w xted against x in Fig. 1, and have been fitted by the method of least-squares to the Redlich–Kister 13type equation
njy1
Dn sx 1yx B 2 xy1 3Ž . Ž . Ž .ÝD jjs1
Ž .The values of the parameters B of Eq. 3 and the standard deviations d are given in Table 5.j
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–9792
Table 2Relative permittivities, e , for the binary liquid mixtures of C H O with CH Cl , CHCl , CH ClCH Cl, CHClCCl andr 6 10 2 2 3 2 2 2
c-C H at T s303.15 K6 12
x e x e x e x er r r r
( )x C H Oq 1y x CH Cl6 10 2 2
0.0356 9.502 0.2155 12.730 0.4597 15.472 0.7751 17.2180.0694 10.198 0.2629 13.387 0.4956 15.756 0.8441 17.4600.0882 10.566 0.3035 13.902 0.5516 16.148 0.9238 17.7090.1069 10.920 0.3449 14.386 0.6035 16.4610.1413 11.528 0.3892 14.844 0.6452 16.6770.1709 12.026 0.4432 15.332 0.7225 17.024
( )x C H Oq 1y x CHCl6 10 3
0.0400 5.710 0.2504 10.335 0.4935 13.845 0.7577 16.2420.0838 6.820 0.2982 11.164 0.5325 14.281 0.8061 16.5970.1163 7.596 0.3442 11.889 0.5804 14.755 0.8697 17.0360.1616 8.595 0.3983 12.667 0.6420 15.315 0.9163 17.3550.2018 9.417 0.4434 13.248 0.6925 15.739
( )x C H Oq 1y x CH ClCH Cl6 10 2 2
0.0399 10.790 0.2992 14.503 0.5960 16.970 0.8626 17.8520.1011 11.809 0.3466 15.020 0.6259 17.119 0.9111 17.9170.1240 12.172 0.3902 15.451 0.6399 17.188 0.9231 17.9240.1681 12.824 0.4422 15.912 0.7075 17.4610.2194 13.532 0.4737 16.160 0.7608 17.6340.2554 13.990 0.5454 16.658 0.8258 17.790
( )x C H Oq 1y x CHClCCl6 10 2
0.0483 4.340 0.2785 7.848 0.5307 10.435 0.7184 12.5660.0927 5.170 0.3297 8.425 0.5534 10.671 0.7915 13.6330.1401 5.968 0.3814 8.970 0.5655 10.796 0.8329 14.3240.1875 6.678 0.4293 9.445 0.6197 11.360 0.8923 15.4580.2370 7.343 0.4748 9.891 0.6733 11.989 0.9332 16.335
( )x C H Oq 1y x c-C H6 10 6 12
0.0618 2.723 0.3110 5.409 0.5575 8.434 0.8079 12.9030.1115 3.277 0.3639 5.981 0.6176 9.338 0.8654 14.2360.1589 3.783 0.4254 6.698 0.6582 10.002 0.8962 15.0120.2098 4.322 0.4709 7.266 0.7041 10.817 0.9380 16.1280.2668 4.935 0.5215 7.930 0.7549 11.780
The values of the changes of relative permittivities on mixing, De , for the various mixtures ofr
C H O were calculated from the relative permittivities e of the mixtures, using the relation6 10 r
Dese yÝ x e ) 4Ž .r i r , i
where e ) refers to the relative permittivity of the pure component i. De has been plotted against xr,i r
in Fig. 2, which shows that throughout the entire range of x , De is highly positive for x C H Oqr 6 10Ž . Ž . Ž .1yx CH Cl , x C H Oq 1yx CHCl , and x C H Oq 1yx CH ClCH Cl, and highly2 2 6 10 3 6 10 2 2
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–97 93
Table 3Refractive indices, n for binary liquid mixtures of C H O with CH Cl , CHCl , CH ClCH Cl, CHClCCl , andD 6 10 2 2 3 2 2 2
c-C H at T s303.15 K6 12
x n x n x n x nD D D D
( )x C H Oq 1y x CH Cl6 10 2 2
0.0363 1.4206 0.2464 1.4296 0.4230 1.4358 0.6510 1.44180.0628 1.4215 0.2662 1.4308 0.4623 1.4368 0.7819 1.44450.1403 1.4256 0.2996 1.4316 0.5143 1.4384 0.8302 1.44500.1904 1.4280 0.3762 1.4342 0.5835 1.4394 0.9361 1.4474
( )x C H Oq 1y x CHCl6 10 3
0.0586 1.4402 0.2716 1.4418 0.4710 1.4432 0.7508 1.44580.0928 1.4405 0.2987 1.4420 0.5393 1.4435 0.8061 1.44650.1346 1.4408 0.3294 1.4424 0.5703 1.4438 0.8864 1.44780.1842 1.4412 0.3832 1.4426 0.6476 1.4444 0.9216 1.44820.2168 1.4414 0.4364 1.4430 0.7141 1.4452
( )x C H Oq 1y x CH ClCH Cl6 10 2 2
0.0550 1.4400 0.1850 1.4414 0.4618 1.4440 0.8050 1.44720.0968 1.4402 0.2976 1.4422 0.5218 1.4448 0.8285 1.44750.0980 1.4404 0.3607 1.4426 0.6216 1.4455 0.8449 1.44780.1135 1.4405 0.4136 1.4435 0.6743 1.4460 0.8955 1.44820.1732 1.4410 0.4331 1.4438 0.7463 1.4466 0.9569 1.4488
( )x C H Oq 1y x CHClCCl6 10 2
0.0519 1.4702 0.3061 1.4650 0.5425 1.4598 0.8628 1.45200.1471 1.4685 0.3655 1.4640 0.6189 1.4580 0.8946 1.45120.1841 1.4678 0.4378 1.4626 0.7188 1.4558 0.9373 1.45050.2353 1.4665 0.5044 1.4610 0.8063 1.4535 0.9519 1.4500
( )x C H Oq 1y x c-C H6 10 6 12
0.0561 1.4218 0.3337 1.4290 0.5834 1.4370 0.8143 1.44400.1226 1.4232 0.3836 1.4306 0.5996 1.4374 0.8421 1.44500.1608 1.4236 0.4194 1.4315 0.6830 1.4400 0.9148 1.44640.2238 1.4262 0.4705 1.4332 0.6961 1.4404 0.9385 1.44720.2715 1.4272 0.4803 1.4340 0.7354 1.4418
Table 4Ž . Ž .Values of the parameter A of Eq. 1 , and the standard deviations d e for the various mixtures at Ts303.15 Kj r
Ž .Mixture A A A A d e1 2 3 4 r
Ž .x C H Oq 1y x CH Cl 8.7114 22.8106 y21.0473 7.4709 0.00476 10 2 2Ž .x C H Oq 1y x CHCl 4.6240 28.1457 y23.4037 8.5758 0.00486 10 3Ž .x C H Oq 1y x CH ClCH Cl 10.0654 18.6363 y13.4826 2.7255 0.00526 10 2 2Ž .x C H Oq 1y x CHClCCl 3.3283 22.2435 y26.9246 19.3048 0.00526 10 2Ž .x C H Oq 1y x c-C H 2.0020 12.1049 y7.1705 11.0061 0.00526 10 6 12
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–9794
Fig. 1. Plot of Dn against the mole fraction of C H O, x , for the following systems at T s303.15 K: \,D 6 10Ž . Ž . Ž . Žx C H Oq 1y x CH Cl ; I, x C H Oq 1y x CHCl ; (, x C H Oq 1y x CH ClCH Cl; v, x C H Oq 1y6 10 2 2 6 10 3 6 10 2 2 6 10
. Ž .x CHClCCl ; ^, x C H Oq 1y x c-C H .2 6 10 6 12
Ž . Ž .negative for x C H Oq 1yx c-C H . For x C H Oq 1yx CHClCCl , De is positive at6 10 6 12 6 10 2 r
low x values, and negative at high x values, and inversion of sign from positive to negative valuesof De for this system occurs at x;0.39. The relative permittivity data are found to exhibit positiver
w xdeviations 14 from values arising from a mole fraction average for chloroformqpyridine where astrong intermolecular complex is formed on account of the hydrogen-bond interaction between thecomponents in the liquid state. The positive values of De for the mixtures of C H O with CH Cl ,r 6 10 2 2
CHCl and CH ClCH Cl may thus be interpreted as indicating that C H O forms strong intermolec-3 2 2 6 10
ular complexes with CH Cl , CHCl and CH ClCH Cl in the liquid state. On the other hand, the2 2 3 2 2Ž .highly negative values of De for x C H Oq 1yx c-C H may be interpreted as indicating ther 6 10 6 12
absence of any specific interaction between the components of this system. The positive values of DerŽ .at low values of x for x C H Oq 1yx CHClCCl indicate the existence of specific interactions6 10 2
Ž .between C H O and CHClCCl . The negative values of De for x C H Oq 1yx CHClCCl at6 10 2 r 6 10 2
high values of x may be interpreted as indicating the predominance of non-specific interactions over
Table 5Ž .Values of the parameters B of Eq. 3 and the standard deviations d for the various mixtures at Ts303.15 Kj
Mixture B B B B d1 2 3 4
Ž .x C H Oq 1y x CH Cl 0.016423 y0.007714 y0.002608 y0.006984 0.000296 10 2 2Ž .x C H Oq 1y x CHCl y0.004508 y0.0053637 0.0043238 0.005020 0.000096 10 3Ž .x C H Oq 1y x CH ClCH Cl y0.0002838 0.0012429 y0.001295 0.000146 10 2 2Ž .x C H Oq 1y x CHClCCl 0.002767 y0.002585 y0.008017 0.002689 0.000186 10 2Ž .x C H Oq 1y x c-C H y0.002073 0.009760 y0.005169 y0.009298 0.000276 10 6 12
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–97 95
Fig. 2. Plot of De against the mole fraction of C H O, x , for the following systems at T s303.15 K: ^,r 6 10Ž . Ž . Ž . Žx C H Oq 1y x CH Cl ; v, x C H Oq 1y x CHCl ; \, x C H Oq 1y x CH ClCH Cl; (, x C H Oq 1y6 10 2 2 6 10 3 6 10 2 2 6 10
. Ž .x CHClCCl ; I, x C H Oq 1y x c-C H .2 6 10 6 12
specific interactions in the higher concentration range of C H O. The specific interaction of C H O6 10 6 10
with CH Cl , CH ClCH Cl, CHCl and CHClCCl can be explained as being due to the formation2 2 2 2 3 2
of a hydrogen bond on account of the interaction of hydrogen atoms in CH Cl , CH ClCH Cl,2 2 2 2
CHCl and CHClCCl with the lone-pair electrons on the oxygen atom of C H O, as it is also3 2 6 10w xknown 15,16 that a complex is formed through hydrogen bonding between dimethylketone and
CHCl . There is, however, also a possibility of involving CH Cl , CH ClCH Cl, CHCl and3 2 2 2 2 3
CHClCCl in the formation of charge-transfer complexes with C H O, owing to the interaction of2 6 10
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–9796
Cl atoms in these chloro-compounds with the lone-pair electrons of C H O, since the halogens are6 10w x w xknown 17 to act as s-acceptors towards electron-donor components. It has been pointed out 18 that
Ž .in the formation of complexes of tetrachloromethane CCl with aromatics, CCl acts as s-acceptor,4 4
the acceptance of electron being made in the empty 3-d level of Cl atoms in CCl .4
4. List of Symbols
A Parameters of polynomial expansion fitting the relative permittivity data for mixturesj
AR Analytical reagentB Parameters of Redlich–Kister type equation fitting the values of Dnj D
e Relative permittivityr
e ) Relative permittivity of pure componentr
e ) Relative permittivity of pure component ir,i
De Deviation of the relative permittivity of the mixture from the value arising from ther
mole fraction mixture lawŽ .d e Standard deviation in er r
GLC Gas liquid chromatographyH E Excess molar enthalpym
HPLC High performance liquid chromatographyi Component iK Kelvinn Refractive indexD
n) Refractive index of pure componentD
n) Refractive index of pure component iD,i
Dn Deviation of the refractive index of the mixture from the value arising from the moleD
fraction mixture lawn-donor Lone-pair electron donorT Temperatureu Ultrasonic velocityuv UltravioletV E Excess molar volumem
x Mole fraction of C H O6 10
x Molar fraction of component ii
s Sigmad Standard deviation in the values of Dn from those obtained from the Redlich–KisterD
Ž .type Eq. 3
Acknowledgements
The authors gratefully acknowledge the financial support received from the Council of Scientificand Industrial Research, New Delhi, India.
( )J. Nath, S.K. MishrarFluid Phase Equilibria 145 1998 89–97 97
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