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Kirkpatrick, R. James Hou, Xiaoqiang 2015-09-28T15:12:26Z 2015-09-28T15:12:26Z 10000-01-01 2001 2001 Layered double hydroxides (LDHs) are a complex group of phases with wide ranging technological applications and increasingly recognized geochemical significance. They are unusual among oxide and hydroxide phases in having large anion exchange capacities, and enhancing their application and understanding their geochemical significance require better understanding of the interlayer and surface structure and dynamics of anions and water molecules. This thesis describes a systematic experimental investigation of the hydration, expansion, and molecular scale structure and dynamics of LDHs. It provides important, fundamental data and significant new insight into the factors that control the observed structural and dynamic behavior. The diversity of LDHs allows incorporation of many NMR-observable nuclei and thus systematic investigation of the effects of such parameters as anionic size, charge, and configuration on the structure and dynamics. I have synthesized a wide variety of LDHs containing the cations Mg,Al and Li,Al in the octahedral layers and anions including 13CO32-, 15NO 3-, 77SeO42- , 77SeO32-, 35ClO4-, 35Cl -, H31PO42-, 31PO43- and many others. These samples were examined with NMR, XRD, TGA and water gravimetry under well-controlled relative humidity conditions or/and over a wide temperature range. The results show that LDHs have widely variable hydration, expansion, structural and dynamical behaviors that depend on the anion size, charge, and configuration, and on the hydroxide-layer composition. The results illustrate clearly how NMR spectroscopy combined with XRD, water sorption and thermogravimetric (TGA) data can effectively probe these properties and provide a basis for understanding the interaction and relationships among these properties. Chapter 1.3 provides a detailed summary of the principal results. Made available in DSpace on 2015-09-28T15:12:26Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3030438.pdf: 7204315 bytes, checksum: 2bc19a85338c0564b2beefa149fa96a3 (MD5) Previous issue date: 2001 Embargo set by: Seth Robbins for item 87800 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 148 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2001. http://hdl.handle.net/2142/86519 (MiAaPQ)AAI3030438 eng Chemistry, Nuclear Structure and Dynamics of Layered Double Hydroxides text Geology Geology University of Illinois at Urbana-Champaign Dissertation Ph.D.