Journal of Chemical Thermodynamics, Vol.32, No.9, 1257-1263, 2000
Excess enthalpies of (benzene plus benzene-d(6)), (cyclohexane plus cyclohexane-d(12)) and (dichloromethane plus dichloromethane-d(2)) at T=298.15 K
Precise and accurate values of the excess enthalpies of {xC(6)H(6) + (1 - x)C6D6}, {xC(6)H(12) + (1 - x)C6D12} and {xCH(2)Cl(2) + (1 - x)CD2Cl2} have been determined over the whole composition range at T = 298.15 K. Although all the excess enthalpies are small, those of {xC(6)H(6) + (1 - x)C6D6} and (xC(6)H(12) + (1 - x)C6D12) are endothermic and those of {xCH(2)Cl(2) + (1 - x)CD2Cl2} are exothermic. A Linear correlation is found between the excess enthalpies at x = 0.5 and the reciprocal of the number of deuterium atoms bound to the carbon atoms of a deuterated compound.
Keywords:deuterium isotope effect;excess enthalpy;benzene-d(6);cyclohexane-d(12);dichloromethane-d(2)