Date of Award

5-2006

Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)

Department

Chemistry

Advisor

Howard Patterson

Second Committee Member

Bruce L. Jensen

Third Committee Member

Carl P. Tripp

Abstract

This thesis compares the interaction of silver(1) dicyanide and gold(1) dicyanide in pure crystals with silver interactions in faujasite type zeoIites. The interaction of gold with silver has been analyzed by luminescence, Raman, crystallography and ab initio caIculations. Metallophilic interactions of four KAUxA1-x(CN)2H2O (x =O.22, 0.20, 0.09, 0.01) heterometallic compounds were investigated through' structural, vibrational, luminescence, and theoretical studies. As the crystal system is changed from rhombohedra] to trigonal, the dominant species shown is a trinuclear mixed metaI cluster supported by solvent molecules. IR and Kaman spectra confirm the purity of linear dicyanometallates, and splitting of the Πg(M-CN) bending mode to an Ag/Bg external pair shows evidence of a gold-silver heterometailic interaction. Luminescence properties of single crystals were investigated from 4K to 298K, and two emissive states due to Ag-Au species at 343 and 372 nm were observed. DFT calculations were performed on the localized clusters within the crystal showing a distinct difference in energy between the four trinuclear structure possibilities and a direct metal-metal interaction in the LUMO structure of each model of KAg(CN)2 and KAu(CN)2. The interaction of silver with the zeolite has been investigated by luminescence, tunneling electron microscopy, and computation. The metal-metal interactions of silver ions within the zeolite matrix were investigated for their interaction with a solvent. The silver-exchanged zeolite was shown to cluster when subjected to tunneling electrons and when kept in the dark during and after preparation little clustering of silver species was found. The excitation spectrum shows specific small clusters present within the silver doped zeolite before exposure to solvent and light. The reactions of silver zeolite with methanol showed an excitation spectrum which included mainly the excitation of the bound silver ion and a red shift in the emission spectrum. Theoretical results indicate as the silver interacts with the solvent in the presence of light the zeolite conduction band electrons cause silver species to become neutral and cluster within the pores while reacting with the solvent.

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