PHOTOLUMINESCENT PROPERTIES AND MOLECULAR-STRUCTURE OF [(AU(PPH3))2(MU-BBZIM)] AND [(AU(PPH3))4(MU-BBZIM)][CLO4]2 (BBZIM = 2,2'-BIBENZIMIDAZOLATE)

The tetranuclear [(Au(PPh3)}4(mu-bbzim)][ClO4]2 and dinuclear [{Au(PPh3)}2(mu-bbzim)] complexes with 2,2'-bibenzimidazolate (bbzim) as bridging ligand have been characterized by X-ray crystallography. The intramolecular Au-Au separations in [{Au(PPh3)}4(mu-bbzim)][ClO4]2 are 3.157(1)-3.222(1) angstrom. Upon excitation at 330 nm, both complexes display intense intraligand fluorescence and phosphorescence in fluid solution at room temperature.