Conformational isomerism of n-butyl nitrate studied by microwave spectroscopy

Stephens, Susanna L.

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https://hdl.handle.net/2142/104375 Copy

Description

Title

Conformational isomerism of n-butyl nitrate studied by microwave spectroscopy

Author(s)

Stephens, Susanna L.

Contributor(s)

• Novick, Stewart E.
• Cooke, S.A.
• Blake, Thomas A.
• Brauer, Carolyn
• Signore, Joshua A.

Issue Date

2019-06-18

Keyword(s)

Conformers and isomers

Abstract

The rotational spectrum of n-butyl nitrate was measured with a chirped pulse Fourier transform microwave \mbox{spectrometer} over the range of 7-13 GHz. This allowed for the identification and assignment of five conformers, AGA, GAA, GGA, AAA, and GG'A with intensity ratios of approximately 1 : 0.2 : 0.2 : 0.1 : 0.1. These conformers were \mbox{subsequently} investigated by Balle-Flygare Fourier transform microwave spectroscopy in order to resolve the nuclear \mbox{electric} quadruople coupling splitting and for further transitions to be collected, allowing improved fitting. Isotopic \mbox{substitutions} at natural abundance were also observed for the AGA conformer. Quantum chemical calculations reveal that the AGA \mbox{conformer} is the lowest in energy. A variety of computational methods were used to explore the energy ordering and barriers between inter-conversion of the lowest lying energy conformers. This work extends a series of other alkyl nitrate works studied by microwave and mm-wave spectroscopy.\footnote{Methyl Nitrate; W.B. Dixon, E.B. Wilson, {\it{J. Chem. Phys.}}, {\bf{35}}, 191 (1961)} \footnote{Ethyl Nitrate; D.G. Scroggrin, J.M. River, E.B. Wilson, {\it{J. Chem. Phys.}}, {\bf{60}}, 1376 (1974); J. Thomas, I. Medvedev, D. Dolson, ISMS 2014} \footnote{n-Propyl Nitrate; W. Orellana, S.L. Stephens, S.E. Novick, S.A. Cooke, C. Brauer, T.A. Blake, ISMS 2019} \begin{center} \includegraphics[width=0.95\textwidth] {nBN.eps} \end{center}

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

eng

Permalink

http://hdl.handle.net/2142/104375

DOI

https://doi.org/10.15278/isms.2019.TJ03

Copyright and License Information

Copyright 2019 Susanna L. Stephens

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