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The energy of combustion of crystalline 1,2,3,4-tetrachlorodibenzo-p-dioxine (-5122.9 ± 7.4 kJ/mol) was measured using an isothermic-shell calorimeter with a rotating platinum plated bomb. The result was used to calculate the enthalpy of combustion (-5120.4 ± 7.4 kJ/mol) and formation (−267.8 ± 7.6 kJ/mol) for the crystalline state. The enthalpy of sublimation was measured using a Calvet microcalorimeter at 411.5 K (116.0 ± 2.6 kJ/mol); recalculation to T = 298.15 K gave 118.7 ± 2.6 kJ/mol. The enthalpy of formation of 1,2,3,4-tetrachlorodibenzo-p-dioxine in the gas state was calculated (−149.1 ± 8.0 kJ/mol)

The standard molar enthalpy of combustion of 2-chlorodibenzo- p -dioxin was redetermined using the sample of high purity by rotating-bomb calorimetry: Δ c H 0 m (cr)=−(5558.2±3.5) kJ · mol −1 . The values of standard molar enthalpies of formation were derived for crystalline and gaseous states: Δ f H 0 m (cr)=−(187.9±3.8) kJ · mol −1 and Δ f H 0 m (g)=−(90.7±3.8) kJ · mol −1 .

The standard molar energy of combustion of fullerene C70 was measured at T=298.15 K by means of a static bomb isoperibolic macrocalorimeter, Δ c U 0 m ( cr )=−(29998±32) kJ · mol −1 . The standard molar enthalpies of formation of fullerene C70 in the crystalline and gaseous states were calculated from the experimental data, Δ f H 0 m ( cr )=(2452±33) kJ · mol −1 and Δ f H 0 m ( g )=(2652±34) kJ · mol −1 . The average CO2 fraction in the combustion products was equal to (0.9995±0.04) of theoretical.

The standard molar enthalpy of combustion of dibenzo- p -dioxin (DD) was measured at T = 298.15 K by static-bomb combustion calorimetry: ΔcHmo(cr) = − (5723.8 ± 1.4)kJ · mol − 1. The standard molar enthalpy of sublimation of this compound was measured by microcalorimetry: ΔcrgHmo = (91.45 ± 0.76)kJ · mol − 1. These values were used to derive the standard molar enthalpies of formation of DD in the crystalline and gaseous states: ΔfHmo(cr) = − (141.6 ± 2.1)kJ · mol − 1and ΔfHmo(g) = − (50.1 ± 2.2)kJ · mol − 1. The specially obtained sample of DD of high purity {mole fraction x = (0.9999 ± 0.0001)} was used in all measurements.

The standard molar enthalpy of combustion of hydrofullerene C60H36 was determined by static bomb calorimetry, ΔcH°m = −(29769 ± 25) kJ·mol-1. Using this result and the standard molar enthalpy of sublimation, ΔsubH°m = (175 ± 5) kJ·mol-1, the values of the standard molar enthalpies of formation of C60H36 in the crystalline and gaseous states were calculated: ΔfH°m(C60H36, cr) = (1013 ± 26) kJ·mol-1 and ΔfH°m(C60H36, g) = (1188 ± 26) kJ·mol-1. The enthalpy of reaction C60H36(g) = C60(g) + 36 H(g) was found to be (9196 ± 30) kJ·mol-1, or (255.4 ± 0.8) kJ·mol-1 per one C−H bond. The enthalpy of reaction C60F36(g) + 36 H(g) = C60H36(g) + 36 F(g) was calculated, ΔrH°m = (1421 ± 203) kJ·mol-1, or (39.5 ± 5.6) kJ·mol-1 per one H atom. The enthalpies of bond breaking and of F to H replacement were compared with the analogous values in some other organic compounds.

The standard massic energies of combustion of three alkyl-derivative of adamantane were measured atT = 298.15 K by static-bomb combustion calorimetry. The standard molar enthalpies of formation in the liquid and gaseous states were obtained from these data. The enthalpies of some reactions of isomerization were calculated from the equilibrium study and compared with the results of calorimetric measurements.

The standard molar enthalpy of combustion of fluorinated fullereneC60F48 was determined by rotating-bomb calorimetry,ΔcHmo = − (24638 ± 163)kJ · mol − 1. Using this result and the standard molar enthalpy of sublimation,ΔsubHmo = (109 ± 7)kJ · mol − 1, the values of the standard molar enthalpies of formation of C60F48in the crystalline and gaseous states were found to be − (7563 ± 166)kJ · mol − 1and − (7454 ± 166)kJ · mol − 1, respectively. The enthalpy of reaction C60F48(g) = C60(g) + 48F(g) was calculated,ΔrHmo (298.15 K) = (13800 ± 167)kJ · mol − 1, orΔrHmo (298.15K ) / 48 = (287.5 ± 3.5)kJ · mol − 1.

The standard massic energies of combustion of eight polycyclic compounds were measured atT=298.15 K by static-bomb combustion calorimetry. The standard enthalpies of vaporization and sublimation were measured in a Calvet microcalorimeter, or adiabatic vaporization calorimeter, or derived from ebulliometric measurements of the vapour pressure as a function of temperature. The standard molar enthalpies of formation in the condensed and gaseous states were obtained from these data. The peculiarities in the strain energies of polycyclic compounds are discussed.

The standard molar enthalpy of combustion of crystalline 2,3-dichlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry: ΔcHm°=−(5406.4±6.6) kJ·mol−1. Using this result and the standard molar enthalpy of sublimation, ΔsubHm°=(108.6±1.0) kJ·mol−1, the values of the standard molar enthalpies of formation of 2,3-dichlorodibenzo-p-dioxin in the crystalline and gaseous states were found to be −(220.5±6.8) kJ·mol−1and −(111.9±6.9) kJ·mol−1, respectively. The standard molar enthalpy of formation of gaseous 2,3,7,8-tetrachlorodibenzo-p-dioxin was estimated: ΔfHm°(g)≈−164.6 kJ·mol−1.

The standard molar energy of combustion of pure fullerene C 60 was measured using a static-bomb isoperibolic macrocalorimeter: Δ c U m o = − (25965 ± 12) kJ·mol −1 . This result was confirmed by recovery of carbon dioxide in the combustion products.

The standard molar energy of combustion of crystalline 2-chlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry: ΔcUm°= −(5573.6±2.8)kJ·mol−1. The standard molar enthalpy of sublimation was measured in a Calvet microcalorimeter: ΔsubHm°= (97.24±0.55) kJ·mol−1. Using these results, the values of the standard molar enthalpies of formation of 2-chlorodibenxo-p±dioxin in the crystalline and gaseous states were found to be −(171.3 ±3.2)kJ·mol−1and −(74.1±3.3)kJ·mol−1and −(74.1-3.3)kJ·mol−1, respectively.

The order-disorder and glass formation processes occurring in some solid organic compounds with cage structures and in some solid halogen-ethanes have been studied by low-temperature calorimetry. The thermodynamic data have been used together with the results of other physicochemical experiments to interpret the molecular processes which occur during the phase transformation.

The standard molar enthalpy of combustion of fluorofullerene C60F36 was determined by rotating-bomb calorimetry, ΔcH°m = −24692 ± 199 kJ·mol-1. Using this result and the standard molar enthalpy of sublimation, ΔsubH°m = 139 ± 8 kJ·mol-1, the values of the standard molar enthalpies of formation of C60F36 in the crystalline and gaseous states were found to be −5362 ± 201 kJ·mol-1and −5223 ± 201 kJ·mol-1, respectively. The enthalpy of reaction C60F36(g) = C60(g) + 36F(g) was calculated, ΔrH°m(298.15 K) = (10617 ± 202) kJ·mol-1, or 294.9 ± 5.6 kJ·mol-1 per one C−F bond. The comparison with the enthalpy of reaction C60F48 = C60(g) + 48F(g), ΔrH°m(298.15 K) = 287.5 ± 3.5 kJ·mol-1 per C−F bond leads to a preliminary conclusion that C−F bond enthalpy decreases with amount of F atoms attached to the fullerene cage.

Enthalpies of combustion of cis - and trans -1-methyl-1,2-dicyclopropylcyclopropane have been measured in a static bomb calorimeter. Enthalpies of formation have been derived for the isomers in the liquid and gaseous states.

The enthalpies of formation of dibenzo-p-dioxin and its polychlorinated derivatives have been measured, and a complete set of the enthalpies of formation has been constructed.

The energy of combustion of perfluoro-2,7-dimethyloctane has been measured in a rotating bomb calorimeter, Δ c U 0 (1) = −3198.2 ± 8.6 kJ mol −1 . The enthalpy of formation, Δ f H 0 (1) has been obtained by combination of the experimental data with the accepted values for the enthalpies of formation of water, carbon dioxide and aqueous hydrofluoric acid.

Data on the thermochemistry of haloethanes are surveyed. The most reliable standard enthalpies of formation of 37 haloethanes are recommended on the basis of a critical analysis of the experimental results published up to 1980 inclusive (and partly in 1981). The constants of a computational scheme for the estimation of the enthalpies of formation of hitherto uninvestigated haloethanes have been evaluated by the method of least squares. The enthalpies of formation of 210 haloethanes containing H, F, Cl, and Br have been calculated with the aid of these constants. The bibliography includes 131 references.

The energy of combustion at 298.15 K of liquid 1,2-dichlorotetrafluoroethane has been determined by rotating-bomb calorimetry. The standard enthalpy of formation derived from these measurements. Δ f H 0 (CF 2 ClCF 2 Cl(g), 298.15 K) = −(937.0±7.3) kJ mol −1 , is in satisfactory agreement with the value calculated previously using the energy of combustion of the gaseous compound.

The energy of combustion of 1,1,2-trifluoro-1,2,2-trichloroethane has been determined with the aid of two rotating-bomb calorimeters. The values of ΔHfo(C(CF2ClCFCl2), 1, 298.15 K) = −(745.0±4.3) kJ mol−1 and ΔHfo(CF2ClCFCl2, g, 298.15 K) = −(716.8 ± 4.3) kJ mol−1 were calculated. Using these values the enthalpy of formation of trifluorochloroethylene: ΔHfo(CF2 CFCl, g, 298.15 K) = −(512.0±4.7) kJ mol−1, has been obtained.

The heat capacity of 1,1,1-trifluoro-3-chloropropane and 1,1,1,3-tetrachloropropane from 12 to 300 K and also the temperature and enthalpy of fusion of these compounds were measured in a vacuum adiabatic calorimeter. The results obtained were used for calculating the thermodynamic functions from 12 to 300 K and, in conjunction with literature data, for calculating ΔG f o (l, 298.15 K). 1,1,1-Trifluoro-3-chloropropane was found to undergo two solid-phase transitions, one transition being monotropic ( T = (116.0 ± 0.1) K; ΔH ′ t = −(605 ± 9) cal th mol −1 ), and the other, enantiotropic ( T = (169.8 ± 0.1) K; ΔH ″ t = (1073 ± 4) cal th mol −1 ). Only one solid-phase transition was found for 1,1,1,3-tetrachloropropane ( T = (219.9 ± 0.1) K; ΔH ″ t = (527 ± 4) cal th mol −1 ). Raman, i.r., and n.q.r. spectra of various phases point to the association of the observed solid-phase transitions with the transformations of conformers.

The energies of combustion of two isomers of trifluorochlorobromoethane have been determined by rotating-bomb calorimetry. The values of the enthalpies of formation: ΔHfo(CF3CHClBr, g) = −(690.4 ± 4.9) kJ mol−1 and ΔHfo(CF2BrCHFCl, g) = −(644.8 ± 6.4) kJ mol−1 were derived. Using the latter value, the enthalpy of formation of trifluorochloroethylene CF2:CFCl was found to be −(500.0 ± 6.5) kJ mol−1.

The heat capacities of 1,1,2,2-tetrafluoro-1,2-dichloroethane and 1,1,2-trifluoro-1,2,2-trichloroethane were measured from 8 to 300 K by adiabatic calorimetry and the thermodynamic functions were calculated from the results. Two phase transitions were found in the crystalline CF 2 ClCF 2 Cl. The conclusion was made, using i.r. spectra, that one of them: T ′ tr = (109.3 ± 0.2) K, Δ H ′ tr = (1212 ± 13) J mol −1 , was associated with the conformer transformations and the other: T ″ tr = (134.6 ± 0.1) K, Δ H ″ tr = (2628 ± 3) J mol −1 , with the formation of plastic crystal. Only one solid-phase transition was found in CF 2 ClCFCl 2 : T ″ tr = (82.5 ± 0.5) K, Δ H ″ tr = (830.9 ± 7.9) J mol −1 . This anomaly was probably caused by the onset of axial rotation of the molecules. The zero entropy of CF 2 ClCFCl 2 was found to be equal 10.1 J K −1 mol −1 . An assumption was made that a disorder of crystal II at T = 0 had a conformational nature.

Energies of combustion of dimethylperfluoroglutarate and perfluoro-di- n -amyl ether have been determined with a rotating-bomb calorimeter and enthalpies of formation at 298.15 K have been derived for the compounds in the liquid and gaseous states. The results are: dimethylperfluoroglutarate, ΔH f o (l) = −468.4 kcal th mol −1 and ΔH f o (g) = −455.9 kcal th mol −1 ; perfluoro-di- n -amyl ether, ΔH f o (l) = −1143.2 kcal th mol −1 and ΔH f o (g) = −1131.9 kcal th mol −1 . The influence of electrophilic group interactions on ΔH f o of oxygen-containing organofluorine compounds is discussed.

The standard molar enthalpy of formation of CF2 = CFCl(g) at 298.15 K derived from new measurements of the energy of combustion of liquid samples of the substance is − (505.5 ± 4.7) kJ · mol−1 in satisfactory agreement with two previous indirectly derived values.

The advances in the thermochemistry of organic compounds, mainly cyclic and organohalogen derivatives, are examined. Studies on the thermodynamics of the polymerisation reactions of cyclic compounds, the determination of the standard enthalpies of formation of cyclic and organohalogen compounds, and the determination of relations between the standard enthalpies of formation and the strain energies of molecules, on the one hand, and their structure, on the other are analysed in detail. The bibliography includes 213 references.