Molybdate-Templated Luminescent Silver Alkynyl Nanoclusters: Total Structure Determination and Optical Property Analysis.

Two novel MoO 4 2- -templated luminescent silver alkynyl nanoclusters with 20-nuclearity ([(MoO 4 2- )@Ag 20 (C≡C t Bu) 8 (Ph 2 PO 2 ) 7 (tfa) 2 ]·(tfa - ) ( 1 )) and 18-nuclearity ([(MoO 4 2- )@Ag 18 (C≡C t Bu) 8 (Ph 2 PO 2 ) 7 ]·(OH) ( 2 )) (tfa = trifluoroacetate) were synthesized with the green light maximum emissions at 507 and 516 nm, respectively. The nanoclusters were investigated and characterized by single-crystal X-ray crystallography, electrospray ionization mass spectrum (ESI-MS), X-ray photoelectron spectroscopy, thermogravimetry (TG), photoluminescence (PL), ultraviolet-visible (UV-vis) spectroscopy, and density functional theory calculations (DFT). The two nanoclusters differ in their structure by a supplementary [Ag 2 (tfa) 2 ] organometallic surface motif, which significantly participates in the frontier molecular orbitals of 1 , resulting in similar bonding patterns but different optical properties between the two clusters. Indeed, both nanoclusters show strong temperature-dependent photoluminescence properties, which make them potential candidates in the fields of optical devices for further applications.