On the relation between isotope effects on vapour pressure and molecular structure

Central Research Institute for Physics, Budapest, Hungary., Hungary..

Abstract

A comparative analysis of available experimental data of the isotope effects on the vapour pressure of polyatomic liquid compounds is given. As a common basis for comparison the reduced temperature scale is used.

The variations in the vapour pressure ratio with the reduced temperature have a nearly identical shape for isotopic substitutions of the same character in the same radicals of different compounds or in compounds having identical structures.

For some groups of compounds a linear relation ship is found between the isotopic effects related to the same value of the reduced temperature scale and the reciprocal square roots of the molecular weights.