Binding of deuterium to icosahedral nickel and cobalt clusters

Abstract

The binding of deuterium atoms to icosahedral nickel and cobalt clusters in the 55 to 147 atom size region is studied at near room temperature conditions. The icosahedral clusters have closed shells at 55 and 147 atoms and closed subshells at many intermediate sizes. Deuterium saturation levels are determined for many of the closed shell and subshell clusters in this size region. From the series of saturation levels a set of binding rules (appropriate to room temperature conditions) have been determined that allow a prediction of the observed coverages for the entire series of closed shell and subshell clusters. The configurations of D-atom binding sites for clusters containing 55, 71, 83, 92, 101, 116, and 147 atoms are given. In general, the ratio of D atoms to surface metal atoms is near unity.