Ligand-induced change of the crystal structure and enhanced stability of the Au11 nanocluster†
In this paper, we report a highly stable gold nanocluster co-protected by the selenophenol and 1,5-bis(diphenylphosphino)pentane (L5 for short) ligands, formulated as [Au11(L5)4(SePh)2]+. The structure of this nanocluster is determined by X-ray crystallography. The L5-ligands are in the form of “Au–PPh2(CH2)5Ph2P–Au”, similar to the “staple motif” in the Aun(SR)m nanoclusters. The purity of this nanocluster is confirmed by electrospray ionization mass spectrometry (ESI-MS) and the thermogravimetric analysis (TGA). Moreover, we have also systematically investigated the stability of the [Au11(L5)4(SePh)2]+ (Au11-Se for short). The results show that Au11-Se is significantly more stable than both Au11(PPh3)7Cl3 (Au11-7 for short) and [Au11(PPh3)8Cl2]Cl (Au11-8 for short), even in the presence of excess thiol (RSH). This work will provide a new opportunity for future wide research on gold nanoclusters.