Physical Chemistry, Short Talk
PC-023

Analysis of the High Resolution Infrared Spectrum of Monodeutero-oxirane

K. Keppler1, S. Albert1*, Z. Chen1,2*, C. Manca Tanner1*, G. Seyfang1*, A. Brandenberger3*, M. Perrino3*, J. Stohner3*, G. Wichmann4*, M. Quack1*
1Departement Chemie und Angewandte Biowissenschaften, ETH Zürich, 8093 Zürich, Switzerland, 2College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China, 3ICBT, ZHAW, 8820 Wädenswil, Switzerland, 4Departement Chemie und Angewandte Biowissenschaften, ETH Zürich, 8093 Zürich,

Monodeutero-oxirane (c-C2H3DO) is of fundamental interest in the context of the concept of isotopic chirality, which introduces a completely new isotope effect arising from the parity violating weak nuclear force [1−3]. It is also of astrophysical interest because of its recent detection towards IRAS 16293-2422B, based on our high resolution spectroscopic results [4, 5]. We have previously reported the analysis of GHz and THz c-C2H3DO [4, 6] and trans-c-CHD-CHDO [7] spectra, and have provided a first high resolution analysis of  the infrared spectra of the two c-C2H3DO fundamentals at  896.025 cm-1 and 837.36 cm-1 [6].  Here we report new measurements of the infrared spectrum of improved newly synthesized samples of c-C2H3DO (room temperature, Doppler-limited resolution), making possible the extension of our analysis towards the two lowest frequency fundamentals, as well as further stronger fundamentals, combination and overtone bands throughout the mid- to near-infrared range, using our Bruker IFS 125 HR ETH-SLS 2009 Prototype (MOPD=11.7m) [4, 8, 9]. We have used our improved molecular parameters for the ground state of c-C2H3DO [6] to carry out the rovibrational analysis in several regions of interest and shall report on the current status of our analysis, including a discussion of the tetrad of the lowest four fundamentals with possible rovibrational interactions. The results will also be discussed as they pertain to ab initio calculations [6, 10] isotopic chirality, molecular parity violation, and the evolution of biomolecular homochirality [1, 9, 11]. We thank G. Matmon for his help with the experiments, F. Merkt for his continued support, and the SNF and the EU for financial support (COST COSY, ERC advanced grant).

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