Unprecedented Pt−Pt Bonded Trimer {[Pt₂Cu₄(C⋮CPh)₈]}₃ Showing Unusual Near-Infrared Luminescence

Abstract

The homoleptic high-nuclearity platinum−copper acetylide complex of stoichiometry [PtCu2(C⋮CPh)4] crystallizes in at least three different polymorphic forms. Dark violet-green crystals with metallic reflectance have been shown by an X-ray diffraction study to be formed by discrete trimers of an hexanuclear octahedral cluster unit {[Pt2Cu4(C⋮CPh)8]}3 stabilized by two unsupported Pt−Pt interactions [2.995(1) Å]. The photoluminescence behavior of this complex which is dramatically influenced by strong axial Pt···Pt interactions either in solid state or in solution (CH2Cl2 298, 77 K) has been studied.