Isotopic Partition Function Ratios Involving H2, H2O, H2S, H2Se, and NH3

Ideal gas phase isotopic partition function ratios involving both deuterium and tritium substitution for hydrogen and also heavy atom substitution in H2, H2O, H2S, H2Se, and NH3 have been calculated at a number of temperatures. The results have been least squares fitted to a five term series in powers of (300/T). Various correction factors to the harmonic approximation were considered in the calculation of the partition function ratios. It is demonstrated that the tabulated ratios can be used to calculate equilibrium constants for isotopic exchange reactions.