A New Technique for the Determination of Heats of Sublimation of Slightly Volatile Substances

Abstract

A technique is described which enables one to measure relative vapor pressures by measuring the rate of change of transmissivity of thin deposits as they are formed by condensation from the vapor. From the temperature dependence of this rate the heat of sublimation of slightly volatile substances can be determined. In the case of graphite, deposits of the order of 0.1 μg per cm² can be detected.