Reduction-resistant [Au25(cyclohexanethiolate)18]0 with an icosahedral Au13 core

Abstract

Cyclohexanethiolate-protected gold cluster Au25(c-HT)18 was isolated for the first time as a minor byproduct of [Au23(c-HT)16]1. Single-crystal X-ray structure analysis revealed that Au25(c-HT)18 has an icosahedral Au13 core, in sharp contrast to the face-centered cubic cores in major products such as [Au23(c-HT)16]1 and Au28(c-HT)20. Au25(c-HT)18 prefers a neutral state to an anionic state, probably because the Au13 core is forced to deform due to the steric hindrance between the c-HT ligands.