PNNL

Abstract

Photoelectron spectroscopy and theoretical calculations are used to elucidate the structure of the Au32- cluster. Although density functional calculations suggest that the high symmetry Ih cage structure of Au32 remains to be the lowest in energy for Au32- at 0 K, the calculated photoelectron spectrum of a low-lying amorphous structure (C1) is found to agree best with the experiment. Free energy calculations show that the C1 structure becomes the most stable isomer at higher temperatures, indicating the importance of entropy in determining the stability of clusters at finite temperatures.