A Caltech Library Service

Rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C_4H_9CN) between 2 and 400 GHz

Wehres, Nadine and Hermanns, Marius and Wilkins, Olivia H. and Borisov, Kirill and Lewen, Frank and Grabow, Jens-Uwe and Schlemmer, Stephan and Müller, Holger S. P. (2018) Rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C_4H_9CN) between 2 and 400 GHz. Astronomy and Astrophysics, 615 . Art. No. A140. ISSN 0004-6361.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present high-resolution rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C_4H_9CN). 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 of ^(14)N 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.

Item Type:Article
Related URLs:
URLURL TypeDescription
Wehres, Nadine0000-0001-8881-2916
Wilkins, Olivia H.0000-0001-7794-7639
Müller, Holger S. P.0000-0002-0183-8927
Alternate Title:Rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C4H9CN) between 2 and 400 GHz
Additional Information:© 2018 ESO. Article published by EDP Sciences. Received 9 March 2018; Accepted 10 April 2018; Published online 27 July 2018. 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.
Funding AgencyGrant Number
Deutsche Forschungsgemeinschaft (DFG)SFB 956
Fulbright FoundationUNSPECIFIED
Subject Keywords:laboratory: molecular – techniques: spectroscopic – radio lines: ISM – ISM: molecules – astrochemistry
Record Number:CaltechAUTHORS:20180808-154946156
Persistent URL:
Official Citation:Rotational spectroscopy of the two conformers of 3-methylbutyronitrile (C4H9CN) between 2 and 400 GHz Nadine Wehres, Marius Hermanns, Olivia H. Wilkins, Kirill Borisov, Frank Lewen, Jens-Uwe Grabow, Stephan Schlemmer and Holger S. P. Müller A&A, 615 (2018) A140 DOI:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:88676
Deposited By: Tony Diaz
Deposited On:09 Aug 2018 14:41
Last Modified:03 Oct 2019 20:09

Repository Staff Only: item control page