A series of trinuclear copper(I) thiolate complexes, [Cu-3(mu -dppm)(3)(mu -SR)(2)]BF4 (R = C6H4Cl-4, C6H4CH3-4, C6H4OCH3-4, C6H4(OCH3)(2)-3,4, C6H4-benzo-15-crown-5, or Bu-t), [Cu-3(mu -dppm)(3)(mu (3)-(SBU)-B-t)](BF4)(2), and [Cu-3(mu -dppm)(3)(mu (3)-SR)(mu (3)-Cl)]BF4 (R = C6H4CH3-4, (C6H4Bu)-Bu-t-4, or C6H4(CH3)(3)-2,4,6) and two hexanuclear copper(I) selenolate complexes, [Cu-6(mu -P<^>P)(4)(mu (3)-SePh)(4)](BF4)(2) (P<^>P = dppm, (Ph2P)(2)NH), have been synthesized, and their photophysical properties have been studied. The X-ray crystal structures of both copper(I) selenolate complexes have been determined. These complexes have been shown to exhibit long-lived low-energy emission in solution, attributed to an excited state of predominantly ligand-to-metal charge-transfer [chalcogenolate to copper(I)] origin.