Synthesis and Photophysical Properties of T-Shaped Coinage-Metal Complexes.

The photophysical properties of a series of T-shaped coinage d metal complexes, supported by a bis(mesoionic carbene)carbazolide (CNC) pincer ligand, are explored. The series includes a rare new example of a tridentate T-shaped Ag complex. Post-complexation modification of the Au complex provides access to a linear cationic Au complex following ligand alkylation, or the first example of a cationic square planar Au -F complex from electrophilic attack on the metal centre. Emissions ranging from blue (Cu ) to orange (Ag ) are obtained, with variable contributions of thermally-dependent fluorescence and phosphorescence to the observed photoluminescence. Green emissions are observed for all three gold complexes (neutral T-shaped Au , cationic linear Au and square planar cationic Au ). The higher quantum yield and longer decay lifetime of the linear gold(I) complex are indicative of increased phosphorescence contribution.