Syntheses, Crystal Structures and Terahertz Spectra of Two Copper(I) Complexes Based on Mixed Diimines and Diphosphine Ligands

Two copper (I) complexes with diimine and diphosphine ligands, [Cu-2(Dpq)(2)(dppBz)(2)](SCN)(2).0.5Dpq.3CH(3)OH (1) and [Cu-2(Dppz)(2)(dPPb)(2)](BF4)(2).2CH(3)OH.2H(2)O (2) (Dppz=dipyrido[3,2 - a : 2',3'-c]phenazine, Dpq=pyrazino[2,3-f][1,10]phenanthroline, dppBz=1,2-bis(diphenylphosphino)benzene, dppb=1,3-bis(diphenylphosphine)butane), were prepared in the mixed solution of methanol and dichloromethane. The structure of these two complexes were determined by X-ray single crystal diffraction and characterized by elemental analysis, NMR, FT-IR, UV-Vis absorption spectrum, fluorescence spectrum and terahertz time-domain spectroscopy (THz-TDS). The unit cell of 1 contains two independent metal centers and half uncoordinated Dpq molecule, and similar structures are very rare. However, complex 2 are novel binuclear structure formed by the bisphosphine ligand. Through the analysis of intermolecular forces, 1 is a three-dimensional stacked structure, which contains unique C-S center dot center dot center dot pi interactions. But 2 forms one-dimensional infinite chain through C-H center dot center dot center dot pi and pi center dot center dot center dot pi. The existence of a large number of weak interactions makes the complexes more stable. The emission spectra showed that the peak of complex 1 was at 578 nm, however, complex 2 emitted green light (at 547 nm). The sharp peak at 1.2 THz in THz-TDS spectrum of complex 2 is caused by the interactions of C-H center dot center dot center dot F. CCDC: 1991845, 1; 1991844, 2.