Search for Inversion Splitting of Phosphine
Abstract
Inversion splitting of phosphine molecules has been one of open questions in molecular spectroscopy. A recent calculation predicted that the splitting is 300 kHz and 3 MHz in the v2 = 3 and 4 states [1], where v2 is the vibrational quantum number of the νb{2} mode. We have observed three Q-branch transitions in the 3νb{2} band of phosphine using a comb-referenced sub-Doppler resolution spectrometer [2]. The spectrometer consists of a difference-frequency-generation source and a cavity-enhanced absorption cell with large beam spot size at beam waist to reduce transit-time broadening. The observed spectral linewidths are 150 kHz, but no inversion splitting has been observed. We now try to observe the 4νb{2} - νb{2} hot band. [1] C. Sousa-Silva, J. Tennyson, S. N. Yurchenko, J. Chem. Phys. 145, 091102 (2016). [2] S. Okuda, H. Sasada, J. Mol. Spectrosc., in press (2018).
- Publication:
-
73rd International Symposium on Molecular Spectroscopy
- Pub Date:
- June 2018
- DOI:
- 10.15278/isms.2018.WG09
- Bibcode:
- 2018isms.confEWG09O
- Keywords:
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- Frequency-Comb Spectroscopy