Gas-phase Enthalpies of Formation of Tri-, Tetra and Pentachloroanilines: Combined DFT and Experimental Study

The gas-phase standard molar enthalpy of formation, at T= 298.15 K, of the 2,3,5,6-tetra-chloroaniline was derived as -(10.6 ± 3.2) kJ·mol -1 from the enthalpies of combustion of the crystalline solid, measured by rotating-bomb combustion calorimetry, and its enthalpy of sublimation obtained by Calvet microcalorimetry. The standard molar enthalpies of formation of all the isomers of the trichloro-, tetrachloro- and pentachloroaniline were calculated by computational thermochemistry based on a Density Functional Theory approach. The calculated values show a good agreement with the experimental results available for some of those isomers.