A LUMINESCENT HETEROMETALLIC AU-I-CENTER-DOT-CENTER-DOT-CENTER-DOT-CU-I COMPLEX - SPECTROSCOPIC PROPERTIES AND CRYSTAL-STRUCTURES OF [AU(PPH(3))(C7H5N2)] AND [(AU(PPH(3))(MU-C7H5N2)CU-(MU-C7H5N(2)))(2)] (C7H5N2=7-AZAINDOLATE)

The mono- and tetra-nuclear complexes [AU(PPh(3))(C7H5N2)] 1 and [{Au( PPh(3))(mu-C7H5N2)Cu(mu- C7H5N2)}(2)] 2, the latter containing 7-azain dolate (C7H5N2-) bridging ligands. have been prepared and their crysta l structures determined. The intramolecular Au...Cu and Cu...Cu separa tions in 2 are 3.0104(6) and 2.941(1) Angstrom respectively. Extended- Huckel molecular-orbital calculations revealed a weak Au-1...Cu-1 bond ing interaction but no Cu-1...Cu-1 interaction. In acetonitrile, both complexes display intense intraligand emission at 510 nm upon photoexc itation with UV/VIS fight at room temperature. In the solid state 2 sh ows an emission at 550 nm.