SYNTHESIS, STRUCTURE, PHOTOPHYSICS, TIME-SOLVED EMISSION-SPECTROSCOPYAND ELECTROCHEMISTRY OF LUMINESCENT COPPER(I) ACETYLIDE COMPLEXES

A series of soluble trinuclear copper(I) complexes containing mono- an d bi-capped mu(3)-eta(1)-acetylides [Cu-3(dppm)(3)(mu(3)-eta(1)-C=CR)] (2+) and [Cu-3(dppm)(3)(mu(3)-eta(1)-C=CR)(2)](+) (dppm = Ph(2)PCH(2)P Ph(2), R = Ph or Bu(t)) have been synthesized and shown to exhibit lon g-lived dual luminescent behaviour. Their photophysics and electrochem istry and those of a mixed halide-acetylide capped trinuclear copper(I ) complex Cu-3(dppm)(3)(mu(3)-eta(1)-C=CBu(t))(mu(3)-Cl)](+) have been investigated. The origin of the low-energy emission (lambda(em) 525-7 00 nm) is ascribed to states of ds/l.m.c.t. admixture with large l.m.c .t. (ligand to metal charge transfer) character: The crystal structure of [Cu-3(dppm)(3)(mu(3)-eta(1)-C=CBu(t))][PF6](2) has been determined . The complex consists of an isosceles triangular array of copper atom s with Cu-Cu distances of 2.910(1), 2.941(2) and 3.175(1) Angstrom.