Theoretical study of icosahedral Ni clusters within the embedded-atom method

Abstract

The embedded-atom method is used to study icosahedral ${\mathrm{Ni}}_{\mathit{N}}$ clusters in the size range from 13 to 147 atoms. Two mutually exclusive structures, corresponding to different ways of covering the underlying icosahedral core, are considered and the more favorable of them is determined for each cluster size. A transition from polyicosahedral to multilayered icosahedral structure is found in very good agreement with chemical probe experiments. Enhanced stability is found after the completion of certain caps (umbrellas) in accordance with near-threshold photoionization mass spectra and with molecular adsorption experiments. \textcopyright{} 1996 The American Physical Society.