Theory of Adsorption of the Isotopic Hydrogen Molecules at Low Temperatures

摘要

A theory of adsorption of the isotopic hydrogen molecules is developed where the potential of interaction of the adsorbed molecule with the plane surface is a function of two parameters. The Schrouml;dinger equation is solved for the rotationmdash;vibrational energy levels of the diatomic molecules in the adsorbed state. From these energy levels, isotopic andorthomdash;paraseparation factors and heats of adsorption are calculated by statistical thermodynamics. There is a reasonable correspondence between experimental separation factors and heats of adsorption derived from chromatographic experiments, and those computed from the theory for selected values of the potential parameters. The sequence of relative volatilities of the hydrogen isotopes andorthomdash;paraspecies found experimentally is in accord with that predicted from the theory. Both the separation factors relative toparahydrogen and the heats of adsorption increase in the order;ohyphen;H2, HD, HT,ohyphen;D2,phyphen;D2, DT,phyphen;T2, andohyphen;T2.