Synthesis, spectroscopic, crystal structure and DFT investigation of the Cu(II) complex with mixed 2,2’-dimethylmalonate/2,2'-bipyridine ligands

In this study; a mixed ligand Cu(II) complex, [Cu(Me2mal)(bpy)(H2O)]∙H2O (Me2mal-2= Dimethylmalonate dianion, bpy=2,2'-bipyridine) was synthesized and characterized experimentally and theoretically by IR, UV and single crystal X-ray diffraction. The complex crystallizes in the orthorhombic system with space group Pnnm. In the complex, the Cu center is coordinated by a Me2mal-2 dianion and a bpy molecule, and the N2O2 exhibits square-planar geometry. The axial position was occupied by the water molecule. The crystal packing of the complex is stabilized by O-H…O hydrogen bonds and  interactions. The contribution of hydrogen bonding and  stacking interactions to crystal packing was also investigated. Theoretical calculations using the DFT method were also carried out in this study. DFT (B3LYP/6-31G) and TD-DFT (B3LYP/LanL2DZ) calculation methods were used to obtain the geometric, vibrational and electronic properties of the synthesized complex and the obtained theoretical calculation results and experimental results are presented comparatively in this study.