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Duliba, Edward Paul 2014-12-15T23:17:51Z 2014-12-15T23:17:51Z 10000-01-01 1983 1983 Predictions of the nuclear quadrupole coupling constants for octahedral copper(II) and the applicability of computer simulation methods to extract quadrupole coupling data from EPR of powders were confirmed with ('63)Cu and ('65)Cu doped into MgSO(,4)(.)7D(,2)O as a test case. From orientation-dependent EPR spectra of each isotope, both as oriented single crystals and as powders, the following spin-Hamiltonian is deduced for ('63)Cu: (')H = (beta) B(.)g(.)S(' )+(' )hI(.)A(.)S - g(,n) (beta)(,n) B(.)I(' )+(' )QD(I(,z)('2)-5/4) + QE(I(,x)('2)-I(,y)('2)). The QD value is among the largest known for octahedral Cu(II), as is typical of the octahedral CuO(,6) grouping. For some magnetic field orientations, secondary ((VBAR)(DELTA)m(,I)(VBAR) = 1) and tertiary ((VBAR)(DELTA)m(,I)(VBAR) = 2) transitions are important and the primary ((DELTA)m(,I) = 0) transitions are strongly affected by quadrupolar effects. The powder and single crystal methods yield parameters in good agreement. Solutions of CuC(,20)S(,2)O(,2)H(,22) were also examined and the nuclear quadrupole coupling parameters determined. The nuclear quadrupole coupling constants for a low-spin^square planar cobalt(II) compound were determined by EPR^spectroscopy. Oriented single crystals and powders of Co-^doped {(C(,2)H(,5))(,4)N}(,2)Ni(S(,2)C(,4)N(,2))(,2) were examined and their EPR^spectra interpreted with the following spin Hamiltonian: (')H = (beta) B(.)g(.)S(' )+(' )hI(.)A(.)S - g(,n)(beta)(,n)B(.)I(' )+(' )hQD(I(,z)('2)-63/4) + hQE(I(,x)('2)-I(,y)('2)). The quadrupole coupling parameters are compared with other available examples and the general absence of quadrupolar effects in the EPR of other low-spin cobalt(II) single crystals discussed. Two high-spin amino acids derivatives were also examined. The cobalt doped powder of the low-spin compound, Ni(amben), yielded measurable quadrupole coupling values. Several cobalt complexes, previously unexamined by EPR, were found not to produce EPR signals and are listed. Made available in DSpace on 2014-12-15T23:17:51Z (GMT). No. of bitstreams: 1 8309935.pdf: 2597567 bytes, checksum: b54d3ff1e3c0afb8edddbdfc9c3472a1 (MD5) Previous issue date: 1983 Embargo set by: Seth Robbins for item 70376 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 125 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1983. http://hdl.handle.net/2142/70210 (UMI)AAI8309935 Chemistry, Physical Studies of Nuclear Quadrupole Effects in Transition Metal Complexes by Electron Paramagnetic Resonance text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.