A new heteroleptic phosphorescent cuprous complex supported by a BINAP ligand: synthesis, structure, luminescence properties and theoretical analyses Luminescent cuprous complexes are an important class of coordination compounds due to their relative abundance, low cost and ability to display excellent luminescence. The heteroleptic cuprous complex solvate rac-(acetonitrile-N)(3-aminopyridine-N)[2,2 0 -bis(diphenylphosphanyl)-1,1 0 -binaphthyl-2 P,P 0 ]copper(I) hexafluoridophosphate dichloromethane monosolvate, [Cu(C 5 H 6 N 2 )-(C 2 H 3 N)(C 44 H 32 P 2 )]PF 6 ÁCH 2 Cl 2 , conventionally abbreviated as [Cu(3-PyNH 2 )-(CH 3 CN)(BINAP)]PF 6 ÁCH 2 Cl 2 , (I), where BINAP and 3-PyNH 2 represent 2,2 0bis(diphenylphosphanyl)-1,1 0 -binaphthyl and 3-aminopyridine, respectively, is described. In this complex solvate, the asymmetric unit consists of a cocrystallized dichloromethane molecule, a hexafluoridophosphate anion and a complete racemic heteroleptic cuprous complex cation in which the cuprous centre, in a tetrahedral CuP 2 N 2 coordination, is coordinated by two P atoms from the BINAP ligand, one N atom from the 3-PyNH 2 ligand and another N atom from a coordinated acetonitrile molecule. The UV-Vis absorption and photoluminescence properties of this heteroleptic cuprous complex have been studied on polycrystalline powder samples, which had been verified by powder X-ray diffraction before recording the spectra. Time-dependent density functional theory (TD-DFT) calculations and a wavefunction analysis reveal that the orange-yellow phosphorescence emission should originate from intraligand (BINAP) charge transfer mixed with a little of the metal-to-ligand charge transfer 3 (IL+ML)CT excited state. research papers Acta Cryst. (2020). C76, 177-185 Wang et al. A new heteroleptic phosphorescent cuprous complex 181 research papers Acta Cryst. (2020). C76, 177-185 Wang et al. A new heteroleptic phosphorescent cuprous complex 185

Luminescent cuprous complexes are important coordination compounds due to their relative abundance, low cost and ability to display excellent luminescence. The structures of two CuIP2S-type cuprous complexes, namely, iodido(thiourea-κS)bis(triphenylphosphane-κP)copper(I), [CuI(CH4N2S)(C18H15P)2] or [CuI(TU)(TPP)2] (I), and (2,3-dihydrobenzimidazole-2-thione-κS)iodidobis(triphenylphosphane-κP)copper(I), [CuI(C7H6N2S)(C18H15P)2] or [CuI(DHBIT)(TPP)2] (II), are described. In these two structures, the complex molecules of both are constructed by one copper(I) centre, one iodide ion, two TPP ligands and one thione ligand (TU for I and DHBIT for II). The copper(I) centres of I and II are both located in a distorted CuIP2S tetrahedron and are coordinated by two P atoms from two TPP ligands, one S atom from the thione ligand and the I atom. The UV–Vis absorption and photoluminescence properties of these CuIP2S-type cuprous complexes have been studied using crystalline powder samples. Detailed time-dependent density functional theory (TD-DFT) calculations and wavefunction analysis reveal that the pale-blue–green phosphorescence emission should originate from intra-ligand (TPP for I and DHBIT for II) charge transfer, with a small component of the metal-to-ligand charge transfer 3(IL+ML)CT excited state.