ABSTRACT

Thermochemical and thermophysical studies have been carried out for crystalline 3,4,40-trichlorocarbanilide. The standard (p = 0.1 MPa) molar enthalpy of formation, at T = 298.15 K, for the crystalline 3,4,40- trichlorocarbanilide (TCC) was experimentally determined using rotating-bomb combustion calorimetry, as (234.6 +- 8.3) kJ mol 1. The standard enthalpy of sublimation, at the reference temperature of 298.15 K, was measured by the vacuum drop microcalorimetric technique, using a High Temperature Calvet Microcalorimeter as (182.1 +- 1.7) kJ mol 1. These two thermochemical parameters yielded the standard molar enthalpy of formation of the studied compound, in the gaseous phase, at T = 298.15 K, as (52.5 +- 8.5) kJ mol 1. This parameter was also calculated by computational thermochemistry at M05-2X/6-311++G** and B3LYP/6-311++G(3df, 2p) levels, with a deviation less than 4.5 kJ mol 1 from experimental value. Moreover, the thermophysical study was made by differential scanning calorimetry, DSC, over the temperature interval between T = 263 K and its onset fusion temperature, T = (527.5 +- 0.4) K. A solid solid phase transition was found at T = (428 +- 1) K, with the enthalpy of transition of (6.1 +- 0.1) kJ mol 1. The X-ray crystal structure of TCC was determined and the three-centred N H O@C hydrogen bonds present analyzed.

Compounds

#	Formula	Name
1	ClH	hydrogen chloride
2	CO2	carbon dioxide
3	N2	nitrogen
4	H2O	water
5	O2	oxygen
6	C13H9Cl3N2O	N-(4-chlorophenyl)-N'-(3,4-dichlorophenyl)urea

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	6	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 2			Crystal 2 Crystal 1 Air at 1 atmosphere	DSC	1
POMD	6	Triple point temperature, K ; Crystal 2			Crystal 2 Crystal 1 Air at 1 atmosphere	DTA	1
POMD	6	Triple point temperature, K ; Crystal 2			Crystal 2 Crystal 1 Air at 1 atmosphere	DTA	1
POMD	6	Normal melting temperature, K ; Crystal 1			Crystal 1 Liquid Air at 1 atmosphere	DTA	1
POMD	6	Molar heat capacity at constant pressure, J/K/mol ; Crystal 1	Temperature, K; Crystal 1	Pressure, kPa; Crystal 1	Crystal 1	Small sample (50 mg) DSC	5
POMD	6	Molar heat capacity at constant pressure, J/K/mol ; Crystal 2	Temperature, K; Crystal 2	Pressure, kPa; Crystal 2	Crystal 2	Small sample (50 mg) DSC	32
POMD	6	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 2	Temperature, K; Crystal 2		Crystal 2 Gas	DSC	1
POMD	6	Molar enthalpy, kJ/mol ; Gas	Temperature, K; Gas Pressure, kPa; Gas		Gas	Calvet microcalorimetry	1
RXND	6 1 2 3 4 5	Specific internal energy of reaction at constant volume, J/g				Rotating bomb calorimetry	1

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Energetic studies of urea derivatives: Standard molar enthalpy of formation of 3,4,40-trichlorocarbanilide

da Silva, M. D. M. C. R.[Maria D. M. C. Ribeiro], da Silva, M. A. V. R.[Manuel A. V. Ribeiro], Freitas, V. L. S.[Vera L.S.], Roux, M. V.[MarIa Victoria], Jimenez, P.[Pilar], Davalos, J. Z.[Juan Z.], Cabildo, Pilar, Claramunt, R. M.[Rosa M.], Pinilla, E.[Elena], Torres, M. R., Elguero, J.[Jose]

ABSTRACT