论文部分内容阅读
We report herein a class of superatomic Au13 clusters stabilized by different N-heterocyclic carbenes (NHCs).The clusters show diverse metal surface structures,properties and functions as exemplified by: (1) the first anionic Au13 cluster[Au13(NHC-1)6Br6]-,which has bulky NHC-1 ligands that lead to a rather open metal surface contributing to its high catalytic activity;(2) the tricationic cluster[Au13(NHC-2)5Br2]3+ which has bidentate,benzyl-rich NHC-2 ligands that make it ultra-stable and highly-luminescent,suitable for bio-imaging;and (3) by bearing two pyridyl groups on NHC-3,the dicationic cluster[Au13(NHC-3)9Cl3]2+ exhibits reversible and stable visible absorption and solubility responses to protonation/deprotonation cycles,making it a potential pH sensor (NHC-1 =1,3-diisopropylbenzimidazolin-2-ylidene;NHC-2 =1,3-bis(1-benzyl-1 H-benzimidazol-1-ium-3-yl)propane;NHC-3 =1,3-bis(picolyl)benzimidazolin-2-ylidene).The study nicely demonstrates the importance of ligands in designing metal nanoclusters with desired functionalities.