title: An experimental and theoretical approach of spectroscopic and structural properties of a new chelidamate copper (II) complex.
abstract: The crystal structure of new chelidamate complex of copper (II) ion, [Cu(chel)H2O(pym)]·H2O [chel: chelidamate or 4-hydroxypyridine-2,6-dicarboxylate; pym: 2-Pyridylmethanol] has been determined by single crystal X-ray crystallographic method. The complex was characterized by IR and UV-Vis spectroscopic techniques. The magnetic environment of copper (II) ion has been defined by electron paramagnetic technique (EPR). The central copper (II) ion is six-coordinate with a distorted octahedral geometry, which exhibits Jahn-Teller distortions along one of the O-Cu-O axes with tetragonality of 0.81. Chelidamate behaved as a tridentate ligand was bonded to Cu(II) ion through carboxyl oxygens with nitrogen. The crystal structure is stabilized by O-H⋯O hydrogen bond and π-π interactions. Theoretical calculations have been carried out by using the DFT method. The modeling of copper (II) complex was made by geometric optimization. The geometry optimization and EPR study were carried out using the following unrestricted hybrid density functionals: LSDA, BPV86, B3LYP, B3PW91, MPW1PW91 and HCTH. Frontier molecular orbital energies, absorption wavelengths and excitation energy were computed by time dependent DFT (TD-DFT) method with polarizable continuum model. IR spectra were discussed and compared to other relevant complexes together with theoretical results. The natural charges on the atoms and second-order interaction energies were derived from natural bond orbital analysis (NBO).
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Amasya University, Ipekköy, 05000 Amasya, Turkey. Electronic address: hatice.vural@amasya.edu.tr.
authors.forename: Hatice
authors.initials: H
authors.lastname: Vural
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Ondokuzmayıs University, Kurupelit, 55139 Samsun, Turkey.
authors.forename: İbrahim
authors.initials: İ
authors.lastname: Uçar
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Giresun University, 28100 Giresun, Turkey.
authors.forename: M Serkan
authors.initials: MS
authors.lastname: Soylu
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011725:Pyridines / Q000737:chemistry; D011728:Pyridones / Q000737:chemistry*; D011789:Quantum Theory; D013057:Spectrum Analysis
chemical_list: D056831:Coordination Complexes; D011725:Pyridines; D011728:Pyridones; C042436:chelidamic acid; C534143:4-pyridone; D003300:Copper
keywords: Chelidamic acid; IR; Quantum chemical calculation; UV–Vis; X-ray diffraction