LaO 2 was produced in a pulsed laser-vaporization molecular beam source and studied by mass-analyzed threshold ionization (MATI) spectroscopy and ab initio electronic structure calculations. The calculations included density functional theory, second-order perturbation theory, coupled cluster theory, and complete active space self-consistent field methods. The adiabatic ionization energy of the molecule and vibrational frequencies of the molecule and its cation were measured accurately for the first time from the MATI spectrum. Numerous ionization processes of lanthanum dioxide, peroxide, and superoxide were considered; the 3B 2 ← 4B 2 electronic transition of the dioxide was assigned upon comparison with the observed spectrum. The ionization energy and O-La-O bending frequency of the 4B 2 neutral state are 4.9760 (6)eV and 92cm -1, respectively. The La-O stretching and O-La-O bending frequencies of the 3B 2 cationic state are 656 and 122cm -1, respectively. The 4B 2 state is formed by two electron transfer from lanthanum to oxygen atoms, and the 3B 2 state is produced by the further removal of a lanthanum 6s-based electron.
|Journal||Journal of Chemical Physics|
|State||Published - Jul 21 2012|
Bibliographical noteFunding Information:
We are grateful for the financial support from the National Science Foundation Division of Chemistry (Chemical Structure, Dynamics and Mechanisms, CHE-1012351). We also acknowledge additional support from the donors of the Petroleum Research Fund of the American Chemical Society and the Kentucky Science and Engineering Foundation. This work was supported by the Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, U.S. Department of Energy (DOE) under Grant No. DE-FG02-03ER15481 (catalysis center program). D.A.D. also thanks the Robert Ramsay Chair Fund of The University of Alabama for support.
ASJC Scopus subject areas
- Physics and Astronomy (all)
- Physical and Theoretical Chemistry