A Face-to-Face Dimer of Au3 Superatoms Supported by Interlocked Tridentate Scaffolds Formed in Au18S2(SR)12

A new sulfur-containing gold cluster, Au18S2(STipb)(12), was serendipitously obtained using the bulky thiol, 2,4,6-triisopropylbenzyl mercaptan (TipbSH), as protecting ligands. Single-crystal X-ray diffraction analysis revealed that Au18S2(STipb)(12) has a deformed octahedral Au-6 core clutched by two tridentate S[Au-2(STipb)(2)](3) units in an interlocked manner. Based on density functional theory calculations, we propose that the Au-6 core with two electrons is better viewed as a face-to-face dimer of Au-3(1e) superatoms rather than an electronically closed Au-6(2e) superatom. In situ formation of the sulfide anions (S-2- via C-S bond breakage is ascribed to the steric repulsion between the TipbS ligands.y

Automated summary

The structure of the new sulfur-containing gold cluster Au18S2(STipb)(12) was revealed through single-crystal X-ray diffraction analysis, showing a deformed octahedral Au-6 core clutched by two tridentate S[Au-2(STipb)(2)](3) units in an interlocked manner.