Structural, optical, morphology characterization and DFT studies of nano sized Cu(II) complexes containing schiff base using green synthesis

In the present work on coordinating chemistry, new Cu(II) complexes have been synthesized from the regular reflux and ball mining methods using Schiff base prepared via condensation of 2-hydrazino-2-oxo-N-phenylacetamide with 2-Hydroxy-1-naphthaldehyde. All of the synthesized compounds were analyzed by various techniques, such as magnetic-moment measuring techniques, FT-IR, H-1 and C-13 NMR, UV/Vis spectroscopy and TGA. Field emission scanning electron spectroscopy (FE-SEM) and EDX were using for determination of size and morphology of the nano metal complexes. Molar conductance studies have confirmed the non-electrolytic nature of the metal complexes. The obtained FT-IR data supports the binding of Cu ion to Schiff base. Different mode of cleation and ratio of ligand towards Cu(II) by change method of preparation. The geometry of free ligand has been optimized at the same level of DFT calculations as the complexes studied in order to compare their data with that of the complexed ligand. The optimization results in addition to spectroscopic and magnetic measurements show that the Cu(II) center is square planner for the [Cu(L)Cl] while octahedral for [CuH2LCl2(H2O)(2)] complexes. Mulliken charges determine the distributions of charges on donor and acceptor atoms. The charge distribution shows that during complex formation the ligands transfer their negative charges to Cu(II) ions. In the gas phase, the electronic excitation energies of Cu(II)complexes are measured using time-dependent functional density theory (TD-DFT). There is a decrease in (Eg) values after complexation with Cu(II), indicating that (Eg) increase upon complexation with metal ions. (C) 2020 Elsevier B.V. All rights reserved.