Probing the Electronic and Structural Properties of the Niobium Trimer Cluster and its Mono- and Dioxides. Nb₃O_n^- and Nb₃O_n (n=0-2)

Journal Article · Fri Feb 06 00:00:00 EST 2009 · Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory

DOI:https://doi.org/10.1021/jp809945n· OSTI ID:958492

Zhai, Hua Jin ^[1]; Wang, Bing ^[2]; Huang, Xin ^[2]; Wang, Lai S. ^[1]

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1. Washington State Univ., Pullman, WA (United States)
2. Fuzhou Univ. (China)

We report a photoelectron spectroscopy and density functional theory (DFT) study on the electronic and structural properties of Nb₃^-, Nb₃O^-, Nb₃O₂^-, and the corresponding neutrals. Well-resolved photoelectron spectra are obtained for the anion clusters at different photon energies and are compared with DFT calculations to elucidate their structures and chemical bonding. We find that Nb₃ ^- possesses a C2V (³A₂) structure, and Nb₃ is a scalene Cs (2A'') triangle. Both Nb₃O^- and Nb₃O are found to have C_2V structures, in which the O atom bridges two Nb atoms in a Nb₃ triangle. The ground-state of Nb₃O₂ ^- is found surprisingly to be a low symmetry C1 (1A) structure, which contains a bridging and a terminal O atom. Molecular orbital analyses are carried out to understand the structures and bonding of the three clusters and provide insights into the sequential oxidation from Nb₃^- to Nb₃O₂^-. The terminal NbdO unit is common in niobia catalysts, and the Nb₃O₂^- cluster with a NbdO unit may be viewed as a molecular model for the catalytic sites or the initial oxidation of a Nb surface.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 958492
• Report Number(s): PNNL-SA-66531; 25396; KP1704020; TRN: US1000387
• Journal Information: Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory, Vol. 113, Issue 16; ISSN 1089-5639
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANIONS
ATOMS
BONDING
CATALYSTS
FUNCTIONALS
MOLECULAR MODELS
NIOBIUM
OXIDATION
PHOTOELECTRON SPECTROSCOPY
PHOTONS
SPECTRA
SYMMETRY
Environmental Molecular Sciences Laboratory