Theoretical Isotherms for Physical Adsorption at Pressures below 10−10 Torr
- 1 September 1966
- journal article
- Published by American Vacuum Society in Journal of Vacuum Science and Technology
- Vol. 3 (5), 281-284
- https://doi.org/10.1116/1.1492490
Abstract
Theoretical isotherms for the physical adsorption of argon, nitrogen, and helium on a heterogeneous surface in the pressure range from Torr down to pressures indefinitely low are presented. The calculations are based on adding a single assumption to a model that was successful in correlating experimental data for argon, nitrogen, and helium over a wide range of adsorbents, temperatures and pressures above Torr. The results are compared with an alternative model that postulates a homogeneous surface and are found to be significantly different. It is concluded that experiments should be possible to establish which, if either, of these approaches is useful.