Adsorption of CO on the (110) plane of tungsten; temperature dependence of the sticking coefficient and absolute surface coverages

Absolute coverages and sticking coefficients as functions of both gas and surface temperatures are presented for CO adsorption on the (110) plane of tungsten. For a low temperature layer the CO/W ratio at saturation is 1.1, while that for alpha or beta adsorption is 0.5, indicating some crowding in the low temperature phase at high coverage. Initial sticking coefficients drop with increasing gas or surface temperature but eventually level off at ~ 0.5. Qualitative reasons for this behavior are given.