Estimation of heat capacities of gases, liquids and solids, and heat capacities of vaporization and of sublimation of organic chemicals at 298.15 K

Abstract

We have constructed equations for the correlation and prediction of heat capacities of gases Cp(gas), heat capacities of liquids Cp(liq), heat capacities of solids Cp(solid), the heat capacity of vaporization ΔvapCp, as Cp(gas) − Cp(liq) and the heat capacity of sublimation ΔsubCp, as Cp(gas) − Cp(solid) for organic compounds and a selection of organometallic compounds. These equations are statistically as good as, or better than, previously reported equations. The same independent variables are used in all the equations, and predictions can be made using simple arithmetic. For some processes, an equation that uses the McGowan volume as the only independent variable is found to be useful as a predictive equation, and has the advantage that the McGowan volume can trivially be calculated from structure, no computer software being required.