PPDS12: For Hvap for the liquid-gas phase boundary

Hvap/(0.001×R×Tc) = a1×t1/3 + a2×t2/3 + a3×t + a4×t2 + a5×t6

where t = 1 - T/Tc, Tc is the critical temperature, and R is the gas constant.

Evaluation Results:

The example is for fitted enthalpies of vaporization for benzene.