ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
We report four new electronic transitions of the SrOH free radical, the C˜ 2∏–X˜ 2∑+, D˜ 2∑+–X˜ 2∑+, E˜ 2∑+–X˜ 2∑+, and F˜ 2∏–X˜ 2∑+ transitions. SrOH was prepared in a supersonic jet by laser ablation and spectra were recorded using laser-induced fluorescence. The C˜ 2∏–X˜ 2∑+ excitation spectrum shows complex vibronic structure which is attributed, at least in part, to Renner–Teller activity in the excited electronic state. This is supported by dispersed fluorescence spectra which show substantial bending mode activity in the emission from several different excited vibronic levels. It is suggested that the prominence of nominally forbidden vibrational features arises from a large change in permanent electric dipole moment between the X˜ and C˜ states. In turn, this suggests that the C˜ 2∏ state of SrOH is the analogue of the "reverse-polarized" ∏ states known for the alkaline-earth monohalides, i.e., the highest occupied π orbital points towards the O atom. The D˜ 2∑+–X˜ 2∑+, E˜ 2∑+–X˜ 2∑+, and F˜ 2∏–X˜ 2∑+ spectra are much simpler than the C˜–X˜ system, being dominated by regular structure in the Sr–O stretching vibration. © 1999 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.479065
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