Structural Elucidation and Position Identification of Cu(II) ion in Hexaaquazinc(diaquabismalonto)zincate: Single Crystal EPR and Optical Studies

Single crystal electron paramagnetic resonance (EPR), powder X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) and UV–Visible (UV–Vis) spectroscopy studies of Cu(II) doped in hexaaquazinc(diaquabismalonto)zincate ( HZDMZ ) have been investigated at room temperature. Angular variation of copper hyperfine lines in the three orthogonal planes shows the presence of a single site in substitutional position, with spin Hamiltonian parameters calculated from EPR spectra are g xx = 2.3940; g yy = 2.0919; g -zz = 2.0700; A– xx = 13.85 mT; A yy = 1.79 mT; A zz = 1.39 mT. Molecular orbital coefficients β 2 = 0.765 and ε 2 = 0.275 have been calculated, which reveal a moderately covalent metal–ligand bond. Optical and EPR data have been collaborated to obtain crystal field parameters, admixture and molecular orbital coefficients. Powder XRD, FT-IR and UV–Vis data confirms the structure of host complex and presence of the dopant. Graphic Abstract