Structural prediction of thiolate-protected Au38: a face-fused bi-icosahedral Au core

J Am Chem Soc. 2008 Jun 25;130(25):7830-2. doi: 10.1021/ja802975b. Epub 2008 Jun 3.

Abstract

The lowest-energy structure of thiolate-group-protected Au38(SR)24 is with ab initio computations. A unique bi-isocahedral Au23 core is predicted for the Au38(SR)24 cluster, consistent with recent experimental and theoretical confirmation of the icosahedral Au13 core for the [Au25(SR)18]- cluster. The computed optical absorption spectrum and X-ray diffraction pattern are in good agreement with experimental measurements. Like the "magic-number" cluster [Au25(SR)18]-, the high stability and selectivity of the magic-number Au38(SR)24 cluster is attributed to high structural compatibility between the bi-isocahedral Au23 core and the 18 exterior staple motifs.