Thermochromic Luminescent Nest-Like Silver Thiolate Cluster

A novel discrete open high-nuclearity nest-like silver thiolate cluster complex, [Ag33S3(StBu)(16)(CF3COO)(9)-(NO3)(CH3CN)2](NO3) (1), has been isolated with nitrate and S2- anions acting as structure-directing templates. Its similar nest-like structure has been assembled into an extended layer [Ag31S3(StBu)(16)(NO3)(9)](n) (2) by adjustment of auxiliary ligand. More interestingly, both complexes exhibit temperature-dependent luminescence of high sensitivity with a large fluorescence enhancement (12-fold for 1, 21-fold for 2), which can be easily recognized by the naked-eye (dramatic red-shift Delta = 104 nm for 1, larger Delta = 113 nm for 2 at 77 K compared to those at 298 K). The correlation between luminescent thermochromism and temperature-dependent variation of the coordination modes of template NO3- anion, Ag center dot center dot center dot S and Ag center dot center dot center dot Ag distances are also elucidated through variable-temperature single-crystal X-ray crystal structure (VT-SCXRD) analyses.