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Title: Vibrationally Resolved Photoelectron Spectroscopy of BO- and BO2-: A Joint Experimental and Theoretical Study

Abstract

We report a photoelectron spectroscopy and computational study of two simple boron oxide species: BO– and BO2–. Vibrationally-resolved photoelectron spectra are obtained at several photon energies (355, 266, 193, and 157 nm) for the 10B isotopomers, 10BO– and 10BO2–. In the spectra of 10BO–, we observe transitions to the 2 sigma + ground state and the 2 pi excited state of 10BO at an excitation energy of 2.96 eV. The electron affinity of 10BO is measured to be 2.510 plus/minus 0.015 eV. The vibrational frequencies of the ground states of 10BO– and 10BO, and the 2 pi excited state are measured to be 1,725 plus/minus 40, 1,935 30, and 1,320 plus/minus 40 cm-1, respectively. For 10BO2–, we observe transitions to the 2 pi g ground state and two excited states of 10BO2, 2 pi u and 2 signa u+, at excitation energies of 2.26 and 3.04 eV, respectively. The electron affinity of 10BO2 is measured to be 4.46 plus/minus 0.03 eV and the symmetrical stretching vibrational frequency of the 2 pi u excited state of 10BO2 is measured to be 980 plus/minus 30 cm-1. Both density functional and ab initio calculations are performed to elucidate the electronic structure and chemicalmore » bonding of the two boron oxide molecules. Comparisons with the isoelectronic AlO– and AlO2– species and the closely related molecules CO, N2, CN–, and CO2 are also discussed.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
918464
Report Number(s):
PNNL-SA-53500
Journal ID: ISSN 1089-5639; JPCAFH; 8592; KP1704020; TRN: US0805830
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry A, 111(6):1030-1035; Journal Volume: 111; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AFFINITY; BONDING; BORON OXIDES; ELECTRONIC STRUCTURE; EXCITATION; EXCITED STATES; FUNCTIONALS; GROUND STATES; PHOTOELECTRON SPECTROSCOPY; PHOTONS; SPECTRA; Environmental Molecular Sciences Laboratory

Citation Formats

Zhai, Hua-jin, Wang, Leiming, Li, Si-Dian, and Wang, Lai S. Vibrationally Resolved Photoelectron Spectroscopy of BO- and BO2-: A Joint Experimental and Theoretical Study. United States: N. p., 2007. Web. doi:10.1021/jp0666939.
Zhai, Hua-jin, Wang, Leiming, Li, Si-Dian, & Wang, Lai S. Vibrationally Resolved Photoelectron Spectroscopy of BO- and BO2-: A Joint Experimental and Theoretical Study. United States. doi:10.1021/jp0666939.
Zhai, Hua-jin, Wang, Leiming, Li, Si-Dian, and Wang, Lai S. Thu . "Vibrationally Resolved Photoelectron Spectroscopy of BO- and BO2-: A Joint Experimental and Theoretical Study". United States. doi:10.1021/jp0666939.
@article{osti_918464,
title = {Vibrationally Resolved Photoelectron Spectroscopy of BO- and BO2-: A Joint Experimental and Theoretical Study},
author = {Zhai, Hua-jin and Wang, Leiming and Li, Si-Dian and Wang, Lai S.},
abstractNote = {We report a photoelectron spectroscopy and computational study of two simple boron oxide species: BO– and BO2–. Vibrationally-resolved photoelectron spectra are obtained at several photon energies (355, 266, 193, and 157 nm) for the 10B isotopomers, 10BO– and 10BO2–. In the spectra of 10BO–, we observe transitions to the 2 sigma + ground state and the 2 pi excited state of 10BO at an excitation energy of 2.96 eV. The electron affinity of 10BO is measured to be 2.510 plus/minus 0.015 eV. The vibrational frequencies of the ground states of 10BO– and 10BO, and the 2 pi excited state are measured to be 1,725 plus/minus 40, 1,935 30, and 1,320 plus/minus 40 cm-1, respectively. For 10BO2–, we observe transitions to the 2 pi g ground state and two excited states of 10BO2, 2 pi u and 2 signa u+, at excitation energies of 2.26 and 3.04 eV, respectively. The electron affinity of 10BO2 is measured to be 4.46 plus/minus 0.03 eV and the symmetrical stretching vibrational frequency of the 2 pi u excited state of 10BO2 is measured to be 980 plus/minus 30 cm-1. Both density functional and ab initio calculations are performed to elucidate the electronic structure and chemical bonding of the two boron oxide molecules. Comparisons with the isoelectronic AlO– and AlO2– species and the closely related molecules CO, N2, CN–, and CO2 are also discussed.},
doi = {10.1021/jp0666939},
journal = {Journal of Physical Chemistry A, 111(6):1030-1035},
number = 6,
volume = 111,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
  • Photoelectron spectra of rare gas dimers Ar[sub 2], Kr[sub 2], and Xe[sub 2] have been measured using the He I radiation at 584 A with a resolution of 13 meV. All the six ionic states in the He I region have been resolved for the first time, including some of the purely repulsive states. Ionization energies are presented to an accuracy [le]0.003 eV. Dissociation energies ([ital D][sub 0]) of the ionic states are calculated using the best estimate adiabatic ionization energies. The [ital D] [sup 2][Sigma][sub 1/2][ital g][sup +] states of all the dimers are weakly bound, contrary to anmore » earlier theoretical prediction. Part of the vibrational structure of two of the electronic states of Ar[sub 2] has been resolved. For the [ital A] [sup 2][Sigma][sub 1/2][ital u][sup +] state, as many as 14 vibrational excitations are observed. These excitations are assigned to transitions to the higher vibrational levels of [ital v]=32--45. For the [ital B] [sup 2][Pi][sub 3/2][ital g] state, three vibrational structures are resolved and are assigned to [ital v]=2--4 of the ionic state. Accurate values of the spectroscopic constants of these states are presented. The present values are compared with the values available in the literature. The [ital D][sub [ital e]] values for the [ital A] [sup 2][Sigma][sub 1/2][ital u][sup +] and the [ital B] [sup 2][Pi][sub 3/2[ital g]] states are estimated to be 1.361 and 0.104 eV, respectively.« less
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