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arXiv · 2201.09266

Rotational spectroscopy of isotopic oxirane, $c$-C$_2$H$_4$O

Holger S. P. Müller·Jean-Claude Guillemin·Frank Lewen·Stephan Schlemmer
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Abstract

We studied the rotational spectrum of oxirane in a sample of natural isotopic composition in selected regions between 158 GHz and 1093 GHz. Investigations of the isotopologs with one $^{13}$C or one $^{18}$O were the primary focus in order to facilitate searches for them in space. We also examined the main isotopic species mainly to look into the performance of Watson's A and S reductions both in an oblate and in a prolate representation. Even though oxirane is a rather asymmetric oblate rotor, the A reduction in the III$^l$ representation did not yield a satisfactory fit, as was observed frequently earlier for other molecules. The other three combinations yielded satisfactory fits of similar quality among each other; the A reduction in the I$^r$ representation required two parameters less than both S reduction fits.

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Holger S. P. Müller, Jean-Claude Guillemin, Frank Lewen, Stephan Schlemmer. 2022-01-23. Rotational spectroscopy of isotopic oxirane, $c$-C$_2$H$_4$O. https://doi.org/10.1016/j.jms.2022.111584

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