| The techniques of time-of-flight mass spectrometry and pulsed negative ion photoelectron spectroscopy were developed and applied to the study of metal containing clusters. These clusters include the homogeneous metal cluster series Mgn and Zn, the heterogeneous or “mixed metal” clusters LiAln and CuAln, metal-aromatic complexes of the form Con(Benzene)m, and molecular metal oxides such as ZrO, MgO, and ZnO.; Mgn and Znn are revealed by negative ion photoelectron spectroscopy to undergo significant changes in electronic structure in the very small size regime. (n ≤ 20) Photoelectron studies of Mgn indicate that metallic band structure begins in these clusters at about 18 atoms, and the trends in both electron affinity and HOMO-LUMO gap for small Mgn and Znn clusters may be consistently explained by application of an electron shell model.; Photoelectron studies performed on LiAln− are consistent with theoretical predictions describing LiAl13 as an ionic entity with an exterior lithium atom bound to an intact Al13 − cluster anion moiety. Mass spectral and photoelectron studies of CuAln− indicate that the copper atom is often located on the interior of these clusters, radically modifying the electronic energy levels of the naked Aln clusters.; Photoelectron and mass spectral studies performed on Con(benzene) m− cluster anions indicate that both extended decker structures, in which isolated cobalt atoms are separated by benzene molecules, and intact cobalt clusters complexed to a single benzene molecule are formed. Photoelectron spectroscopy indicates that the magnetic moment of Co in Co 1(benzene)2 is reduced relative to the value of the isolated Co atom.; Photoelectron spectroscopic investigations of MgO−, ZnO−, and ZrO−, have provided information on the excited electronic states of these molecules as well as fundamental vibrational frequencies, electron affinities, and dissociation energies. |
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