Electronic structure of SmO and SmO− via slow photoelectron velocity-map imaging spectroscopy and spin-orbit CASPT2 calculations
Abstract
The chemi-ionization reaction of atomic samarium, Sm + O → SmO+ + e−, has been investigated by the Air Force Research Laboratory as a means to modify local electron density in the ionosphere for reduction of scintillation of high-frequency radio waves. Neutral SmO is a likely unwanted byproduct. The spectroscopy of SmO is of great interest to aid in interpretation of optical emission spectra recorded following atmospheric releases of Sm as part of the Metal Oxide Space Cloud (MOSC) observations. Here, we report a joint experimental and theoretical study of SmO using slow photoelectron velocity-map imaging spectroscopy of cryogenically cooled SmO− anions (cryo-SEVI) and high-level spin-orbit complete active space calculations with corrections from second order perturbation theory (CASPT2). With cryo-SEVI, we measure the electron affinity of SmO to be 1.0581(11) eV and report electronic and vibrational structure of low-lying electronic states of SmO in good agreement with theory and prior experimental work. We also obtain spectra of higher-lying excited states of SmO for direct comparison to the MOSC results.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 21, 2017
- Source ID
- 10.1063/1.5008423
Entities
People
- Albert A Viggiano
- Bess Vlaisavljevich
- Daniel Neumark
- Jessalyn A DeVine
- Marissa L Weichman
- Nicholas S Shuman
- Shaun G Ard
- Toru Shiozaki
Organizations
- Air Force Office of Scientific Research
- Air Force Research Laboratory
- Lawrence Berkeley National Laboratory
- Northwestern University
- Yusuf Hamied Department of Chemistry