%0 Journal Article %J Journal of Physics and Chemistry of Solids %D 2020 %T The Au25(SR)18 cluster carrying icosahedral dodecaborate and glutathione ligands: A spectroscopic view %A Eva Valusova %A Maria Kanuchova %A Tomas Base %A Viktor Viglasky %A Marian Antalik %K Chirality %K Coating %K Optoelectronic nanomaterials %K Spectroscopy %X

The functionality of Au25(S-glutathione)18 clusters change when some of the ligands in the cluster shell are replaced for other species. In this study we report on the synthesis and characterisation of a new cluster in which undecahydro-closo-dodecaborate thiolates are introduced as constituents of the shell surrounding the gold core. This is the first reported example in which the Au13 core of the Au25(S-glutathione)18 cluster is covered with an Au–S–B linkage instead of an Au–S–C on the dimeric shell units using a ligand exchange reaction. The spectra of the new cluster species clearly indicate a successful ligand exchange while retaining the gold core with undisrupted semirings containing both thiolate species. The resulting clusters were identified as Au25 [(S-glutathione)18-x (S-closo-borate)x-)] (x = 3, 4). Despite the achiral character of the closo-borate thiolates entering the semiring, increased chirality traces were observed in the high-energy region. Circular dichroism (CD) responses are ligand dependent and provide a fingerprint characteristic of the ligands present in the cluster. The next generation of such surface functionalized clusters provides unique base for computational and application studies.

%B Journal of Physics and Chemistry of Solids %G eng %U https://www.sciencedirect.com/science/article/pii/S0022369720307411?via%3Dihub %9 Primary research article %R https://doi.org/10.1016/j.jpcs.2020.109838