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dc.contributor.authorSliwinski, David R.en_US
dc.date.accessioned2009-10-02T13:19:48Z
dc.date.available2009-10-02T13:19:48Z
dc.date.issued1991-10-02T13:19:48Z
dc.identifier.urihttp://hdl.handle.net/10464/2739
dc.description.abstractA ~si MAS NMR study of spin-lattice relaxation behaviour in paramagnetic-doped crystalline silicates was undertaken, using synthetic magnesium orthosilicate (forsterite) and synthetic zinc orthosilicate (willemite) doped with 0.1% to 20% of Co(II), Ni(II), or CU(II), as experimental systems. All of the samples studied exhibited a longitudinal magnetization return to the Boltzmann distribution of nuclear spin states which followed a stretched-exponential function of time: Y=exp [- (tjTn) n], O<n<l For the most reliable experimental data, there is a bias toward n=O.Sj the few genuine cases of deviation from 1/2power are for dopant concentrations equal to or exceeding 2.5 percent dopant. In some cases we find agreement with theory, and observe a direct proportionality between the spin-lattice relaxation time and paramagnetic dopant ion concentration, with Tni[M2+]i=Tnj[M2+]j for a given dopant and mineral. There are many cases where this correlation is not apparent, however, and this is attributed to the structural, phase, and ion distribution complexities inherent in many of these systems.en_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectNuclear magnetic resonance.en_US
dc.subjectSpin-lattice relaxation.en_US
dc.subjectParamagnetism.en_US
dc.subjectSilicates.en_US
dc.titleA29 NMR spin-lattice relaxation study of paramagnetics -doped orthosilictesen_US
dc.typeElectronic Thesis or Dissertationen_US
dc.degree.nameM.Sc. Chemistryen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Chemistryen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US


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