High-Nuclearity Silver-alkynyl Cluster Encapsulating Two Carbonates Generated from Atmospheric Carbon Dioxide Fixation and Co-protected by Diphenylphosphinate Ligands

For investigating the template effects and the ligand roles in constructing structurally charming silver clusters, we isolated and analyzed a new cluster compound, namely, [(CO 3 ) 2 @Ag 25 (C≡C t Bu) 15 (CF 3 CO 2 ) 3 (Ph 2 PO 2 ) 2 I] , 1 . We report here the synthesis, crystal structure, characterization by various spectroscopic (IR, solid-state NMR, XPS) techniques and the luminescent property of this cluster. Its X-ray crystal structure reveals that the cluster is a 25-nuclearity silver cage with double CO 3 2− ions encapsulated in. Two diphenylphosphinates in new coordination mode (μ 2 :O 1 ,O 1 ) are co-protecting on the surface of cluster 1 . Also, the cluster emits orange-red light in the solid-state at 77 K.