Synthesis, crystal structure and optical limiting property of a novel octanuclear silver cluster complex with an aryl selenolate ligand

The homoleptic silver aryl selenolate complex [Ag-8(2,4,6-(Pr3C6H2Se)-C-i)(8)] 1 was synthesized by the reaction of AgNO3 with an equivalent amount of 2,4,6-triisopropylbenzeneselenol (2,4,6-(Pr3C6H2SeH)-C-i) in MeCN in the presence of triethylamine at room temperature for 4 h. Recrystallization by slow diffusion of CH3OH into a CH2Cl2 solution gave yellow block crystals. The crystal structure determination indicates that the structure of the Ag8Se8 core of complex 1 consists of a compressed distorted Ag-8 hexagonal bipyramid embedded in a distorted rhombohedron formed by eight selenium atoms of the aryl selenolate ligands. The cluster exhibits a strong optical limiting effect with threshold of 0.2 J cm(-2), which is about 2.5 times lower than that of C-60 in toluene under identical experimental conditions.