CALCULATION OF ENERGY ACCOMMODATION COEFICIENT USING SOFT-CUBE MODEL

The analysis of the soft-cube model, a classical model for the interaction of gas atoms with solid surfaces introduced by Logan and Keck 1) is extended to enable the energy accommodation coefficient to be calculated. The theoretical results are compared with some available experimental results for the rare gases on tungsten, covering a wide range of temperature conditions. The soft-cube model includes surface temperature effects, allowing realistic comparison with cases where the solid is at a nonzero temperature. For physically reasonable values of the well-depth and range of the interaction potential good agreement is obtained between theory and experiment. Values of the fraction of gas atoms which are trapped (temporarily) on the surface after collision are calculated, showing the relation between this quantity and the energy accommodation coefficient. © 1969.