About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Paper
Knudsen measurements of the sublimation and the heat of formation of GeSe2 [1]
Abstract
Knudsen effusion studies of the sublimation of polycrystalline GeSe2 have been performed employing mass spectrometry in a temperature range of about 610–750 K and vacuum microbalance techniques in the temperature range 614–801 K and at pressures ranging from about 10−7 − 10−4 atm. The results demonstrate that GeSe2 vaporizes congruently under present experimental conditions according to the predominant reaction (1) GeSe2(s) = GeSe(g) + 1/2 Se2(g) and a minor reaction (2) GeSe2(s) = GeSe2(g). The mean values for the third law heat and second law entropy of reaction (1) based on direct mass‐loss data are ΔH°298 = 70.4 ± 2 kcal/mole and ΔS°298 = 64.7 ± 2 eu. From these the standard heat of formation and absolute entropy of GeSe2(s) were calculated to be −21.7 ± 2 kcal/mole and 24.6 ± 2 eu, respectively. Copyright © 1976 Verlag GmbH & Co. KGaA, Weinheim