Details
| Original language | English |
|---|---|
| Article number | A140 |
| Number of pages | 11 |
| Journal | Astronomy and astrophysics |
| Volume | 615 |
| Early online date | 27 Jul 2018 |
| Publication status | Published - Jul 2018 |
Abstract
We present high-resolution rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C4H9CN). Spectra were taken between 2 and 24 GHz by means of Fourier transform microwave spectroscopy. Spectra between 36 and 403 GHz were recorded by means of frequency modulated (FM) absorption spectroscopy. The analysis yields precise rotational constants and higher order distortion constants, as well as a set of14N nuclear electric quadrupole coupling parameters for each of the two conformers. In addition, quantum chemical calculations were performed in order to assist the assignments. Frequency calculations yield insight into the vibrational energy structure of the two conformers, from which partition functions and vibrational correction factors are determined. These factors are used to determine experimentally and computationally the energy difference between the two conformers, which is revealed to be negligible. Overall, this study provides precise spectroscopic constants for the search of 3-methylbutyronitrile in the interstellar medium. In particular, this molecule is a perfect test case for our knowledge of branched molecule formation in space.
Keywords
- Astrochemistry, ISM: molecules, Laboratory: molecular, Radio lines: ISM, Techniques: spectroscopic
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Astronomy and Astrophysics
- Earth and Planetary Sciences(all)
- Space and Planetary Science
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In: Astronomy and astrophysics, Vol. 615, A140, 07.2018.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C4H9CN) between 2 and 400 GHz
AU - Wehres, Nadine
AU - Hermanns, Marius
AU - Wilkins, Olivia H.
AU - Borisov, Kirill
AU - Lewen, Frank
AU - Grabow, Jens Uwe
AU - Schlemmer, Stephan
AU - Muller, Holger S.P.
N1 - Funding Information: Acknowledgements. We thank Oliver Zingsheim and Dennis Wachsmuth for help during the FTMW measurements in Hannover. We are grateful to Arnaud Belloche for communicating the results of a search for 3-methylbutyronitrile in the EMoCA survey. This work has been supported by the Deutsche Forschungsgemeinschaft (DFG) through the collaborative research grant SFB 956 “Conditions and Impact of Star Formation”, project areas B4 and B3. Olivia Wilkins acknowledges support from a Fulbright U.S. Student Research Award.
PY - 2018/7
Y1 - 2018/7
N2 - We present high-resolution rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C4H9CN). Spectra were taken between 2 and 24 GHz by means of Fourier transform microwave spectroscopy. Spectra between 36 and 403 GHz were recorded by means of frequency modulated (FM) absorption spectroscopy. The analysis yields precise rotational constants and higher order distortion constants, as well as a set of14N nuclear electric quadrupole coupling parameters for each of the two conformers. In addition, quantum chemical calculations were performed in order to assist the assignments. Frequency calculations yield insight into the vibrational energy structure of the two conformers, from which partition functions and vibrational correction factors are determined. These factors are used to determine experimentally and computationally the energy difference between the two conformers, which is revealed to be negligible. Overall, this study provides precise spectroscopic constants for the search of 3-methylbutyronitrile in the interstellar medium. In particular, this molecule is a perfect test case for our knowledge of branched molecule formation in space.
AB - We present high-resolution rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C4H9CN). Spectra were taken between 2 and 24 GHz by means of Fourier transform microwave spectroscopy. Spectra between 36 and 403 GHz were recorded by means of frequency modulated (FM) absorption spectroscopy. The analysis yields precise rotational constants and higher order distortion constants, as well as a set of14N nuclear electric quadrupole coupling parameters for each of the two conformers. In addition, quantum chemical calculations were performed in order to assist the assignments. Frequency calculations yield insight into the vibrational energy structure of the two conformers, from which partition functions and vibrational correction factors are determined. These factors are used to determine experimentally and computationally the energy difference between the two conformers, which is revealed to be negligible. Overall, this study provides precise spectroscopic constants for the search of 3-methylbutyronitrile in the interstellar medium. In particular, this molecule is a perfect test case for our knowledge of branched molecule formation in space.
KW - Astrochemistry
KW - ISM: molecules
KW - Laboratory: molecular
KW - Radio lines: ISM
KW - Techniques: spectroscopic
UR - http://www.scopus.com/inward/record.url?scp=85062844809&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/201832994
DO - 10.1051/0004-6361/201832994
M3 - Article
AN - SCOPUS:85062844809
VL - 615
JO - Astronomy and astrophysics
JF - Astronomy and astrophysics
SN - 0004-6361
M1 - A140
ER -