Structure and Barrier to Methyl Group Internal Rotation for (CF₃)₂CFCF₂OCH₃ and Its Isomer n-C₄F₉OCH₃ (HFE-7100)

Author

Garry S. Grubbs, Missouri University of Science and TechnologyFollow
Stephen A. Cooke

Abstract

The hydrofluoroether C ₄F ₉OCH ₃ (methoxynonafluorobutane, HFE-7100) has been studied by chirped pulse Fourier transform microwave spectroscopy as vapor from the liquid participates in a supersonic expansion of argon. Two isomers are present, (CF ₃) ₂CFCF ₂OCH ₃ and n-C ₄F ₉OCH ₃, and in each case the rotational spectra of only one, dominating, conformer has been assigned. Rotational constants, centrifugal distortion constants, and barriers to methyl group internal rotation for the observed species have been experimentally determined for the first time. We note that Rays asymmetry parameter for the (CF ₃) ₂CFCF ₂OCH ₃ isomer is 0.007 083(1), indicating almost "perfect" asymmetry. Also, electronic structure calculations show an extremely short C(frame)-O ether bond length of 1.337 Å

Recommended Citation

G. S. Grubbs and S. A. Cooke, "Structure and Barrier to Methyl Group Internal Rotation for (CF₃)₂CFCF₂OCH₃ and Its Isomer n-C₄F₉OCH₃ (HFE-7100)," Journal of Physical Chemistry A, vol. 115, no. 6, pp. 1086 - 1091, American Chemical Society (ACS), Jan 2011.

The definitive version is available at https://doi.org/10.1021/jp110390y

Department(s)

Chemistry

International Standard Serial Number (ISSN)

1089-5639

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2011 American Chemical Society (ACS), All rights reserved.

Publication Date

01 Jan 2011