Date of Graduation

Summer 2016

Degree

Master of Science in Chemistry

Department

Chemistry

Committee Chair

Nikolay Gerasimchuk

Keywords

cyanoximes, Ni(II) and Cu(II) complexes, crystallohydrates, TG/DSC, IR-, Uv-Vis spectroscopy, X-ray single crystal analysis, XRD powder diffraction, antiferromagnetic

Subject Categories

Chemistry

Abstract

The design of one-dimensional nickel wires were attempted. Metal complexes of hydrated Cu(II) and Ni(II) with several cyanoximates were synthesized and characterized by elemental analysis, thermal analysis, IR-, electronic- (solid state diffuse reflectance) spectroscopy, and the X-ray analysis (powder diffraction and single crystal studies). Hydrolysis of the HECO and HMeCO cyanoxime ligands leads to the formation of another dianionic cyanoxime – AACO2-, which forms multimetallic Cu(II) and Ni(II) complexes and oxamide as a side product. The crystal and molecular structures of 8 compounds were determined (6 metal complexes and 2 organic compounds). Two Ni metal complexes have distorted octahedral structures with the cyanoximes acting as a chelating ligand, one Cu metal complex has distorted square pyramidal structure and three metal complexes of Cu and Ni were found to be multimetallic with two different environments: penta- and hexa-coordinated which correspond to distorted square pyramidal and octahedral geometries. The trimetallic complexes of Ni(II) and Cu(II) with AACO2- are isostructural. The tri-copper(II) complex demonstrates significant antiferromagnetic interactions between the cyanoxime-bridged metal centers at room temperature. All metal complexes have both coordinated, and crystallization water molecules, which are essential for the crystal packing via the system of H-bonds. The hydrated complexes of Ni(II) of selected cyanoximes were dehydrated, and respective anhydrous complexes were obtained and characterized. Electronic spectroscopy and XRD powder diffraction studies of the anhydrous complexes evidenced the retention of geometry of the central Ni atom after dehydration which suggests bridging function of cyanoximes in the lattices even after water loss. These results show the design of the desired one-dimensional nickel wire systems are feasible. KEYWORDS: cyanoximes, Ni(II) and Cu(II) complexes, crystallohydrates, TG/DSC, IR-, Uv-Vis spectroscopy, X-ray single crystal analysis, XRD powder diffraction, antiferromagnetic

Copyright

© Adedamola Abraham Opalade

Open Access

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Chemistry Commons

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