Anion Photoelectron Spectroscopy of Semiconductor Clusters

Thesis/Dissertation · Mon Dec 01 04:00:00 EST 1997

OSTI ID:764710

Xu, Cangshan ^[1]

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1. Univ. of California, Berkeley, CA (United States); Chemical Sciences Division

Semiconductor and related clusters are studied by anion photoelectron spectroscopy. Vibrationally-resolved photoelectron spectra of carbon (C₄^-, C₆^-, and C₈^-) and silicon (Si₃^- - Si₇^-) clusters were measured at various photodetachment wavelengths. Electron affinities, term energies, and vibrational frequencies for the ground and excited electronic states of the neutral clusters have been obtained. The assignments of excited electronic states were aided by ab initio calculations, as well as measurements of photoelectron angular distributions. Besides clusters of pure elements, mixed group III-V clusters are also investigated. Small indium phosphide clusters having 2-8 atoms are studied using anion photoelectron spectroscopy of In_xP_y^- (x,y=1-4). Both ground and low-lying electronic states of the neutral clusters are observed. Electron affinities a re determined from the spectra. An electronic gap is shown in the even cluster anion spectra. Other related clusters, Si_nH (n=2-4) and PO₂ were also studied. The electron affinities and ground state vibrational frequencies are obtained from the spectral assignments, aided by ab initio calculations and photoelectron angular distributions. The anion geometry of PO₂ is also obtained from Franck-Condon analysis.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Energy Research (ER)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 764710
• Report Number(s): LBNL--41308; NSF DMR--9521805; NSF DMR-9521805
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANGULAR DISTRIBUTION
ANIONS
ATOMS
CARBON
ELECTRONS
GROUND STATES
INDIUM PHOSPHIDES
PHOTOELECTRON SPECTROSCOPY
SEMICONDUCTOR MATERIALS
SILICON
SOLID CLUSTERS
SPECTRA
WAVELENGTHS