Ideal gas state thermodynamic functions for a series of halogenated propenes

27zmnmhimka ACZLZ, IO (1974) 333-344 0 Ek&er Scientific Publishing Company, Amsterdam - Printed in Belgium

IDEAL GAS STATE THERMODYNAMIC FOR A SERIES OF HALOGENATED J. LIELMEZS Chcmicd

AND

FUNCTIONS PROPENi

H- ALEMAN

Engineering

Deponent,

The Unicersity

of Brifish Columbia,

Vancomer.

B.C.

(Canada)

(Received 6 August 1974)

and (HO-HG)jT have been The thermodynamic functions, Ci, S”, -(F”,-N”)IT calculated in the ideal gas state at one atmosphere for the following halogenated propenes: cti-l-chloropropene; rrans-l-chloropropene; cis-I-bromopropcne; trans1-bromopropene; 2-fluoropropene; 2-chloropropene; 2-bromopropene; 2-iodopropene; cis-3-fluoropropene; Buche-34luoropropene; isomer&3-fluoropropene mixture; cis-3-chloropropene; gauche-3-chioropropcne; isomeric-2-chloropropene mixture; cis-3-bromopropene; gauche-3-bromopropene; isomeric-3-bromopropene ITliXtllR; cis-Iiodopropene; gauche-Xodopropene and isomeric-3-iodopropene mixture. The a_greement with other results, whenever available, is very good_ INTRODUCTION

The available spectroscopic and structural data for a series of halogenated pro-penes have made it possible to calculate the thermodynamic properties-heat capacity, entropy, enthalpy and free entry function for c&l-chloropropene; fratzscis-l-bromopropene; l-chloropropene; trmrs-l-bromopropene; 24iuoropropcne; 2-chloropropene; 2-bromopropene; 2-iodopropene; clr-34luoropropene; gauche-3fluoropropene; cis- and gauche-3-fluoropropene equilibrium mixture; cis-3-chlorocis- and gauche-3-chloropropene equilibrium propene; gauche-3-chloropropene; mixture; cis-Zbromopropene; gauche-3-bromopropene; cis- and gauche-fbromopropene equilibrium mixture; cis-Iiodopr0pen.e; gauche-3-iodopropene; cis- and gauche -3-iodopropene equilibrium mixture. The presented thermodynamic functions (Table 1) were calculated by means of the well-known statistical-mechanical methods. The internal rotational barrier contribution was treated by means of the Pitzer-Gwinn or Lielmezs-Boudi2*3 method depending on the availability of the experimental data. The presented results (Table I) are correlated to eqn. (1): A =a+bT+cT’

(1)

where n is the thermodynamic function at temperature T(K). The constants a, b and c (eqn. (1)) were obtained using linear least squares curve fitting methods4 and are

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339 TABLE

3 OF USED

SUMMARY

cis-I-Chioropropene

FREQUENCIES

AND

Zrans-I-ChIoropropene

STRUCTURAL

DATA

cis-I-Bromopropene

mans-I-Eromopropcnc

Fundamental frequencies (cm-‘) 309s: 2960, 1454. 1332, 1033. 797, 564,

3045, 2934, 1448, 1217, 937. 759, 398,

2982 1640 1383 1070 933 690 (225)

3073,= 3034. 2960, 2934, 1456, 1446, 1296, 1247. 1044, 960. 876, 806, 422. 270.

2976 1649 1380 1105 930 757 (220)

3102,= 3034, 2960, 2947. 1456, 1444, 1312, 1212, 1041, 936, 765, 6&1. 494, 382,

2978 1638 1388 1070 925 677 (194)

3078,= 3029,” 2980 2961. 2937, 1637 1461. 1446, 1387 1292, 1225, 1087 1041, 952, 931 743, 729, 677 355, 250. (210)

Principal moments of inertia (gcmz X 103s) I* = 5.91936 Is = 23.1014 fC = 28.5356

z* = 2.0141* II3 = 34.3407 I, = 35.8338

Z, = 6.754ge &I = 32.1740 Ic = 38.4095

I* = 2.0555” lb = 49.6844 Z, = 51.2285

Irea = 0.4695’

Id

Reduced moment of inertia &cm’ X lOa? La

= 0.4661’

I,

= 0.4696

= 0.4712

Internal rotational barrier height (cal mol-l) 602s

2170=

23p

2120s

-

-

-

Isomcrization energy (Cal mol- ‘) symmetly number, Q 1 Mokcular

1

1

1

weight 120

2-Fhuwopropcne

2-Chbropropenc

120.99

2-Bromopropene

2-Io&propene

3115,33010, 2972, 2930, 1443. 1439. 1379, 1170. 996, 925, 680. 551, 335, 301.

3 103.k2994, 2928, 2967, 1457, 1436, 1377, 1159, 991, 926, 701, 514, 318, 271,

Fundamental frequencies (cm-‘) 3141,” 3059, 3012 2975. 2942, 1687 1448, 1448. 1429 1401, 1270, 1048 1008, 944, 862 846, 629, 472 404, 355 (191)

3121,’ 2973. 1450, 1382, 999. 692, 396,

3025, 2940, 1450, 1184, 926, 641, 343,

2992 1645 1412 1046 879 434 (196)

2987 1640 1405 1w5 883 414 (196)

Principal moments of inertia (gun’ x IO39 1, = 17.077’ la = 9.395 z, = S-198

I* = 17.125= la = 8.927 k = 25.536

G = 35.62Jp I, = 8.949 Ic = 27.192

z* =

8.957“ 35.850 1, = 44.291 b

=

2974 1627 1406 1056 W3 389 (195)

340 TABLE

3 (conrkud)

i!-Fiuo~opropene

2-Bronwpropene

2-ro&propene

I@

&,

moment of inertia &cm= x IO39

Reduad ka

Z-Chloropropene

= OS53’

1,

= 0.576”

= 0.584~

= 0.589”

IntemaI rotational barrier height (Cal mol-‘) 2671=’

24uP

komerization energy (Cal mol- I) -

2695D

2700’

-

-

Symmetry number, Q I

I

i

76.53

120.99

167.98

1 MoIecuIii

weight

60.07

cir-3-Fluoropropcne

Fnndamen-d

gauche-3-EXwropropeze

cis-3-Chloropropene

gauche-3-Chloropropene

3091,‘302I. 3018 2987.2940. 1647 1445. 1430, 1291 1290, 1177. 1050 923 1040, 931, 550 795, 712, (94) 513, 253.

3091.* 2987, 1445. 1257. 987. 896, 409.

I* = 19.34s la = 6.708 rc = 25.522

z* =

29.724’

Za =

3.985

Ic = 30.620

I rCQ= 1.046’

&Ul = 1.710.

frequencies (cm-‘)

3092.s 3026. 2990. 2957, 1465, 14I3. 1289. 1240. 1027, 989, 925, 901. 35z 273.

2990 I652 1383 II07 989 601 (163)

309x 2990. 1459, 12S9. 989, 1006_ 432,

3026. 2939, 1426. 1240. 916. 935. 345,

2990 1630 I362 II63 IO27 642 (8s)

3021, 2958, 1412, 1201. 938, 738, 290,

Principal moments of inertia &cm* x 10’4 rA = 4.835= IEa= 139I7 ZC = 18_2?3

I., = 2982” 1, = 19.605 = 20.271 LZ

Reduced moment of inertia (Scm* X IO33 Id

= l-194=

Id

= 1_544=

Internd rotational barrier height (Cal mol-*)

-

-

-

-

-

500.

-

Isoixmizatioil energy (caI mol- ‘) 306Symmetry number, Q I

1

1

1

MoIecuIar weight 60.07

60.07

76.53

76.53

3018 1642 I291 1100 933 590 (56)

341

cis-3-Bromopropene

gauche-3-Bromo-

cis-3-Iodopropene

propene

gauche-3-Iodopropene

Fundamental frequencies (cm-‘) 3OS8,’ 3021, 2983, 2966. 1463, 1408. 1249, 1154, 1040, 926: 810, 695. 456. 215.

3010 1645 1295 lW2 921 543 (89)

3085: 2983, 1442, 1211. 986, 567, 392,

3021, 2966, 1403, 1192, 935, 690, 252,

3010 1631 1295 1072 929 536 (55)

3092: 2984, x4+%, 1201, 981. 825, 420,

3016, 2968, 1420, loss, 932, 669. 197,

2984 1645 1307 1022 920 540 (107)

3092,’ 2984, 1439, 1187, 981, 825, 380,

3016, 2968, 1405, 1150, 932, 669, 232,

I* =

3.48P

le =

60.393

29M 1632 129’ 1050 923 491 (541

Principal moments of inertia (gctn’ x 10z9) I* = 29-524. IB = 7.240 Ic = 36.233

I, = 43.755’ 1, = 4.417 Jc = 45.034

IA = 7.262’ le = 38.188 Ic = 49.919

Ic = 62.948

Reduced moment of inertia (gem* x 1039) rred = 1.113’

I red = 1.959’

-

Internal rotational barrier height (cal mol-‘) Isomer&&on

-

-

-

I600’

energy (caI mol- ‘)

850= Symmetry number, 6 1

I

1

1

Molecular weight 120.99

x20.99

167.89

167.EP

a AI1 frequency values obtained from ref. 5- b This is liquid state (Rarnan spectra) frequency; the same given reference. c All frequency *alues obthxc-3 from ref- 8. d Moments of inertia values cakxlated; this work. Structural data taken from ref. 5. c Moments of inertia v&xs calculated; this work_ Structural data-see ref. 8. ’ Reduced moment of inertia values calculated; this work. Structural data taken from refs. 5, 7. atd 8. * Internal rotational barrier values taken from refs 6 and 9. b All frequencies taken from ret 11. ‘ AU frrquencics taien fi0.Tll ref. 14. ’ All frequencies taken from ret 15_ k AlI frequencies taken from ref. 16. ’ Calculated, this work. Structural data from ref. 13_m Calculated, this work. Structural data from refs. 13 and IA D Calculated, this work. Structural data from refs. 13 aud 15_ o Calculated. this work. Structural data from refs. 13 and 16. P See ref. 12. * Estimated; this work. See the appropriate discussion in the text s Ail frequency and strccturzd data from refs. 19 and 20. c All frequency and structural data from refs. 19 and 23. p Structural and isomerizaticn energy data from ref. 20. v Structural and isomerization energy data from ref. 23. w Isomerization energy calculated from mass cquilibriuxn data. See also ref. 23. x Calculated using estimated mass equilibrium data. See refs. 19 and 23.

found in Table 2. The values of the used molecular parameters for the calculation of the presented thermodynamic functions are given in Tabie 3.

342

I-Chloro- and I-bromopropenes The thermodynamic functions for I-chloro- and I-bromopropenes (Table 1) were cakulated using the infrared frequency assignments of Berg and Elst5; the internal rotational barrier values indicated by Good et al.’ and the available structural data as listed by Beaudet’ for the gaseous state cis- and irrms-l-chloropropenes. The infrared vibrational frequency data of Elst et al.’ supplemented with the internal rotational barrier values as compiled by Good et ah6 and structural data given by Bea.udetgagain for the gaseous state, were used to calculate the thermodynamic functions for ck- and zrrms-1-bromopropenes. TABLE

4

COMPARISON

OF So (cd K-l

mol”)

VALUES

so (cd K-l

AT

mol-

298.15 K

‘) or 298.25 K

77~3 cork (Tile 1)

Rcfm10

Ref. 22

cis-l-Ffwropropcne rrrw-I-FIuoropropene tic-I-ChIoropropene fr~-l-cblolopropute cis-l-Bromopmpcne nuns-I-Bromopmpenc cir-I-xodopropcnc rnzns-I-Iodopropene

-

69.0

-

7022 69.74 72-79 7255 -

69-O

-

71.5 73.5 74.5 74.5 76.7 76.7

-

cfs-3-Fiuoropropene gauche-3-Ruoroprop homer-3-Fluoroprop

6792 69.10 70.88

-

-

70.6

7235

cir-3-ChIoropropene gauche-3KhIoropropene Hsomer-3-Chloropropene

71-43 7243 74.15

73.3

-

cir-3-Bromopropcne gal.lck-3-Bromo~mpenc Iwmcr-3-Bromopropene

74.22 75.20 76.57

75.8

-

cis-3-Iodopropene ;gamfre-EIodoprqse Isomer-3-iodopropauz

75-67 77.01 77_IS

-

-

n-9

If we compare (Table 4) our cakulated entropy values (at 298.15K) with those given by Alfassi et al_“, we note that our values for both l-chloro- and l-bromopropenes are smaHer_However, fWassi et aLzu present the same entropy values for both 1-haIopropene isomers (cI;s-and rrmu-forms). This and the somewhat unclearuse

343 of the additivity methods to obtain theirlo presented entropy values (Table 4) mar the credibility of their results. Thus it seems preferable to use thermodynamic property values obtained directly from gaseous state spectroscopic calculations (Tables l-3). It should be noted that the contribution to the internal restricted rotation for these I-halopropenes was calculated by means of the Pitzer-Gwinn method’. In view of these considerations, the overall calculated thermodynamic function (Table 1) accuracy is estimated to be within l-Z% interval; that is within the experimental error range. 2-Haiopropenes Thermodynamic functions for 2-halopropenes (Table 1) were calculated using the following gaseous state vibrational frequency and structural data values; for 2-fluorcpropene the frequency assignments made by Crowder and Smyrl’ ’ ; the internal rotational barrier value from Benz et al.r2; while the needed C-F distances from the compilation of Bondi and Lielmezs13. For the case of 2-chIoropropenes, the frequency values were taken from Meyer et al. i4, while the internal rotational barrier were taken from Benz et al. 12. For 2-bromopropene the vibrational frequency assignments made by Meyer and Guenthard” were used with the internal barrier value again taken from Benz et aI_f ’ _ Finally, for 2-iodopropene the vibrational frequency assignments of Meyer et al. ’ 6 were used while the value of internal rotational barrier was estimated from the known barriers of 2-fluoro-, 2-&Ioro- and 2-bromopropenes using the observation made by Lielmezs and coworkers’ ‘*I8 that the internal rotational barriers may be correlated with the corresponding substituent atom ionization potentials within the given compound series. The contribution to the internal restricted rotation for all 2-halopropenes was obtained by means of the Pitzer-Gwinn method’ _ Considering the overall reliability of the used spectroscopic and structural data, it is estimated that thermodynamic function values have I-2% accuracy; that is, the calculated values should be within the experimentaI error range. 3-Hdopropenes Thermodynamic functions of the 3-halopropenes were caIcuIated for cis- and rrmrs-forms and the isomeric cis- and Zrrms-form mixtures (Table 1). _Xsthere were not availsble su&ientIy rehable intemai rotational barrier values; but rather it was possible to obtain isomerization energy and torsional frequency values (Table 3) for all 3-halopropenes; the thermodynamic functions (TabIe 1) were then calculated by means of the LieImezs-Bondi2.3 method. For 3-lluoropropenes, the vibrational frequencies were taken from M&a&Ian and Nyquist ’ ’ while the isomerization energy, the structural data and the torsional frequency values were taken from Hirota “_ Table 4 compares the calculated entropy value at 298.15 K between our work; the value obtained by AIfassi et al. lo using the additivity method; and value estimated by Bryce and Lielmezs= ‘_ The agreement between this work and that of Alfassi et al. ’ ’ is excellent. The deviation found in the work

344 of Bryce and Lielmezs’ ’ is explainable noting that Bryce and Lielmezs estimated the fundamental deformation frequencies of 3-fluoropropene from a set of experimental frequency values of 3chloro-, 3-bromo- and 3-iodopropene as given by Thompson and Torkingtonz2. Even so Bryce’s and Lielmezs” results were within their estimated Z-3% uncertainty range. For 3-chloro, 3-bromo- and 3-iodopropenes we used vibrational frequency data, mainly in the liquid state from McLachlan and Nyquist”g and from Sourisseau and Pasquieti3; while the needed isomerization energies were calculated from the known isomer mass rati~s~~-*~_*~_ All the calculated thermodynamic functions are found in Table I ; while the used spectroscopic, thermodynamic and structural data are given in Table 3. Again, Table 4 shows the comparison -between our calculated entropy values for all Zhdopropenes and the values obtained by Alfassi et al-lo using the group additivity method. The agreement for all 3-halopropenes is very good; and we estimate that our results (Table 1) will be well within the error (less than _t 1“A) of our experimental determination_ ACicxowuDGExExa-

The financial assistance of the XationaI fully acknowIedged_

Research Council of Canada is grate-

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