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

Abstract

The homoleptic silver aryl selenolate complex [Ag₈(2,4,6–Pr₃ⁱC₆H₂Se)₈] 1 was synthesized by the reaction of AgNO₃ with an equivalent amount of 2,4,6-triisopropylbenzeneselenol (2,4,6-Pr₃ⁱC₆H₂SeH) 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 Ag₈ 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 C₆₀ in toluene under identical experimental conditions.