Date of Award
Doctor of Philosophy
Robert E. McCarley
This research work involves both solid state and solution chemistry. In the area of solid state chemistry, a number of exciting reduced ternary molybdenum oxides containing both discrete oligomeric cluster units (K[subscript]3Mo[subscript]14O[subscript]22 (1) and BaMo[subscript]5O[subscript]8 (2)) and infinite metal-metal bonded chains (KMo[subscript]4O[subscript]6 (3) and Sr[subscript]0.62Mo[subscript]4O[subscript]6 (4)) were discovered. Compound 1 contains discrete oligomeric units of three trans-edge-shared Mo[subscript]6 octahedra interconnected by Mo-O-Mo bonding to form chains along the monoclinic c-axis. The discrete oligomeric cluster units contained in compound 2 (Ba[subscript]2Mo[subscript]10O[subscript]16) are trans-edge-shared Mo[subscript]10 bioctahedral clusters interconnected along the a-axis of the monoclinic cell. The couplings between oligomeric clusters in compounds 1 and 2 are identical and can be described by the general formula Mo[subscript] 4n+2O[subscript] 6n+2O[subscript]4/2, where n is the number of Mo[subscript]6 octahedra trans-edge-fused together. Compounds 3 and 4 are members of this series with the infinite chain of trans-edge-shared Mo[subscript]6 octahedral cluster units. All the compounds reported so far are structurally characterized by (Mo[subscript]4O[subscript]6) octahedral cluster chains which are coupled through Mo-O-Mo interchain linkages to weave a puckered square pattern (except the case of KMo[subscript]4O[subscript]6 where a square pattern is formed) and form channels parallel to the chain axis in which the ternary metal ions are located;In the area of copper(II) alkoxide chemistry, several interesting complexes with the anion of 2-(2-hydroxyethyl)pyridine (hep) as ligands have been synthesized and structurally characterized. Compounds (CuCl(hep)) [subscript]2 (5), (CuCl(hep)(Hhep)) [subscript]2 ·2CH[subscript]2Cl[subscript]2 (6), and (CuCl(hep)(py)) [subscript]2 ·CH[subscript]2Cl[subscript]2 (7) are doubly bridged copper(II) dimers involving a Cu[subscript]2O[subscript]2 moiety. Compound 5 may also be described more accurately as a polymer of dimers. The dimers are linked in a stairstep fashion along (111) through intermolecular Cu-Cl-Cu linkages. Interestingly, compounds 6 and 7 are each interconvertable with 5. When under reduced pressure, 6, and 7 each lose the apical ligand and CH[subscript]2Cl[subscript]2 solvent to form the polymer of dimers 5. Notably, compound 5 has an extremely strong antiferromagnetic coupling (2J = -1298 ± 138 cm[superscript]-1) between two copper(II) centers within the dimer. In the compound (Cu(hep)[subscript]2 ·LiOS[subscript]3CF[subscript]3) [subscript]2 ·4CH[subscript]2Cl[subscript]2 (8), a cis configuration of two hep ligands about the Cu atom is observed. The Cu(hep)[subscript]2 monomers in 8 are held together through two bridging Li[superscript]+ ions of lithium trifluoromethylsulfonate to form a dimer;The partially characterized compounds K[subscript]0.5M[subscript]1.9Mo[subscript]14O[subscript]22 (M = Ca, Sr, Ba, Pb, and Sn), Ca[subscript] 3-xMo[subscript]14O[subscript]22, Sn[subscript]3.6Mo[subscript]16O[subscript]24, PbMo[subscript]6O[subscript]10, and a novel copper(II) alkoxide complex are also reported in this work. ftn*DOE Report IS-T-1510. This work was performed under Contract W-7405-eng-82 with the Department of Energy.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Chen, Sheng-Chang, "Synthesis and characterization of reduced ternary molybdenum oxides and soluble copper(II) alkoxide complexes " (1991). Retrospective Theses and Dissertations. 9927.