The gas phase reactivity and photochemistry of transition metal complexes and small cluster ions
Abstract
In this thesis, three separate and distinct topics in metal ion chemistry were studied using Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS): (1) the gas-phase chemistry of Fe$\sp+$ and Cu$\sp+$ with linear alkanenitriles, (2) the chemistry of MgFe$\sp+$, and (3) the multiphoton dissociation of MC$\sb4$H$\sbsp{8}{+}$ isomers with M = Ni and Fe. The chemistry of Fe$\sp+$ with linear nitriles was probed using ion-molecule reactions and collision-induced dissociation. These results were compared with collisional activation and metastable ion experiments completed by Schwarz and co-workers. Generally, good agreement existed between the activation methods. A detailed study was also completed on the reactions of Fe$\sp+$ with the n-pentanenitrile isotopomers. A unique reaction mechanism for the elimination of ethylene was determined and two degenerate isomerizations were discovered. After studying Fe$\sp+$ chemistry, the reactions of Cu$\sp+$ with linear nitriles were probed and compared to collisional activation studies. In contrast to Fe$\sp+$, large differences in reactivity were determined between the techniques. Using FTICR, simple ligand attachment products were observed between Cu$\sp+$ and nitriles up to n-hexanenitrile and the elimination of small hydrocarbons and H$\sb2$ commenced with n-octanenitrile. In contrast, Cu(HCN)$\sp+$, Cu(CH$\sb2$CN)$\sp+$, and Cu(CH$\sb2$CHCN)$\sp+$ were observed by CA. The variety of products are explained by differences in the excitation modes. In another study, the gas-phase chemistry of the heteronuclear diatomic metal cluster MgFe$\sp+$ was investigated. While a number of MFe$\sp+$ species (M = transition metal) have been studied in our laboratory, this was the first dimer studied to combine a main group element and a transition metal. The chemistry reflected a weak metal to metal dimer bond when compared to previously studied metal dimer ions. Finally, the multiphoton dissociation of MC$\sb4$H$\sb8\sp+$ (M = Fe, Ni) isomers was studied. The results further characterize and distinguish these isomeric structures.
Degree
Ph.D.
Advisors
Freiser, Purdue University.
Subject Area
Analytical chemistry
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.