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dc.contributor.authorReed, Zachary David
dc.date.accessioned2014-03-04T18:25:19Z
dc.date.available2014-03-04T18:25:19Z
dc.date.issued2009-12
dc.identifier.otherreed_zachary_d_200912_phd
dc.identifier.urihttp://purl.galileo.usg.edu/uga_etd/reed_zachary_d_200912_phd
dc.identifier.urihttp://hdl.handle.net/10724/26136
dc.description.abstractMetal oxide clusters of the form MnOm + (M=Y,La,In), transition metal carbonyl complexes of the form TM-(CO)n + (TM=Mn,Cu,Au), and mixed vanadium benzene carbonyl complexes of the form V-bz-(CO)n + are produced in the gas phase by laser vaporization in a pulsed nozzle and detected with time-of-flight mass spectrometry. The metal oxide clusters are studied using fixed frequency photodissociation. A limited number of stoichiometries are found for each value of n. Clusters are mass selected and photodissociated using the third harmonic (355 nm) of an Nd:YAG laser. Larger clusters undergo fission to produce certain stable cation clusters. Yttrium and lanthanum oxides clusters of the form MO(M2O3)n + are found to be particularly stable, along with Y6O8+. Density functional theory (DFT) calculations were performed to investigate the structures and bonding of these clusters. The stability of some indium oxide clusters, including In5O4+, In5O4+, and In3O2+ can be understood in terms of Wade’s Rules of electron counting. Other indium oxide clusters with enhanced stability do not follow Wade’s Rules, including In3O1+, and In2O+. The carbonyl and mixed benzene-carbonyl complexes are studied using infrared photodissociation spectroscopy and density functional theory. Mn(CO)6+ has a completed coordination sphere, consistent with its expected 18 electron stability. All manganese carbonyl complexes feature red-shifted υCO. The argon tagged analogues of the small (n=1-6) complexes are studied by IRPD. The spin state of small clusters is observed to gradually decrease as additional ligands are added, from a quintet MnCO+ to a singlet Mn(CO)5+. Copper carbonyl cations are observed to have blue-shifted υCO, demonstrating that they are non-classical carbonyls. Cu(CO)4+ has a completed coordination sphere, in line with the 18 electron rule. All small complexes are observed exclusively as singlets, but some triplet population is observed for n=7,8. This is explained in terms of the increased oscillator strengths of the triplets. Au(CO)n+ is demonstrated to have a completed coordination sphere at n=4, despite having significant reduced binding energy for n=3,4. It is also a non-classical carbonyl. V-bz-(CO)n+ is demonstrated to have two different coordination numbers, with n=3 and n=4. Both feature redshifted υCO. The symmetric CO stretch is strongly activated in these complexes.
dc.languageeng
dc.publisheruga
dc.rightspublic
dc.subjectGas phase
dc.subjectlaser vaporization
dc.subjectIR photodissociation
dc.subjectcarbonyl
dc.subjectmetal oxide
dc.subjectclusters
dc.subjectmolecular beams
dc.subjectcarbon monoxide
dc.subjectmetal carbonyl
dc.titleFixed frequency dissociation of metal oxide cations and infrared photodissociation studies of metal carbonyl cation systems
dc.typeDissertation
dc.description.degreePhD
dc.description.departmentChemistry
dc.description.majorChemistry
dc.description.advisorMichael Duncan
dc.description.committeeMichael Duncan
dc.description.committeeCharles Kutal
dc.description.committeeNigel Adams


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