M 3O 4 (M Sc, Y, and La) were produced in a pulsed laser-vaporization molecular beam source and studied by mass-analyzed threshold ionization (MATI) spectroscopy and electronic structure calculations. Adiabatic ionization energies (AIEs) of the neutral clusters and vibrational frequencies of the cations were measured accurately for the first time from the MATI spectra. Five possible structural isomers of M 3O 4 were considered in the calculations and spectral analysis. A cage-like structure in C 3v point group was identified as the most stable one. The structure is formed by fusing three M 2O 2 fragments together, each sharing two O-M bonds with others. The ground electronic state of the neutral clusters is 2A 1 with the unpaired electron being largely a metal-based s character. Ionization of the 2A 1 state yields a 1A 1 ion state in a similar geometry to the neutral cluster. The AIEs of the clusters are 4.4556 (6), 4.0586(6), and 3.4750(6) eV for M Sc, Y, and La, respectively. The observed vibrational modes of the cations include metal-oxygen stretching, metal triangle breathing, and oxygen-metal-oxygen rocking in the frequency range of 200-800 cm -1.
|Journal||Journal of Chemical Physics|
|State||Published - Aug 28 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.
ASJC Scopus subject areas
- Physics and Astronomy (all)
- Physical and Theoretical Chemistry