Crystal structure and emission study of [(PPh3)2Cu(dmp)-O-(dmp)Cu(PPh3)2]2+ (dmp = 2,9-dimethyl-1,10-phenanthroline)

The synthesis and crystal structure of a luminescent dinuclear Cu(I) complex as the BF^–₄ salt from toluene and methanol containing triphenylphosphine and -oxo-bis(2,9-dimethyl-1,10-phenanthroline) is described. The coordination geometry about the Cu(I) center is distorted tetrahedral. An unusual feature of the structure is a pseudo-inversion center located near the oxygen atom at approximately 0.51, 0.26, 0.25, such that all of the atoms except for the oxygen are related by a pseudo-inversion center to another atom in the same molecule, as well as by crystallographic inversion to the other molecule in the unit cell. The complex displays luminescence from an MLCT band in fluid solution and emission from both a metal-centered charge-transfer and intraligand (phenanthroline) state at 77K in a chloroform snow. Crystal data: triclinic, P, a = 15.163(2), b = 16.985(2), c = 18.731(2) Å, = 106.458(9), = 91.416(8), = 102.557(9)°, V = 4496(1) ų, and Z = 2.