Observation Of The Low Energy Conformations Of 1-ethyl-1-fluorosilacyclopentane By Rotational Spectroscopy
Abstract
1-ethyl-1-fluorosilacyclopentane has been synthesized and the pure microwave spectrum has been recorded with a chirped-pulse, Fourier transform microwave spectrometer for the first time. Three different conformers, referred to as axial, equatorial – 1, and equatorial – 2 were identified from quantum chemical calculations and observed in the resultant spectra. The low energy conformers were identified using a relaxed energy scan and optimized using quantum chemical calculations. These optimized structures are reported and compared to experiment where the three observed conformers were all fit to Watson S semirigid Hamiltonians utilizing different combinations of centrifugal distortion terms. Rotational spectroscopic parameters for isotopologues of each conformer are reported. For the axial conformer, a complete heavy atom experimental structure (excluding fluorine) was determined. All structures are then compared to a family of molecules using planar moments of inertia analysis.
Recommended Citation
J. S. Jebaraj et al., "Observation Of The Low Energy Conformations Of 1-ethyl-1-fluorosilacyclopentane By Rotational Spectroscopy," Journal of Molecular Spectroscopy, vol. 420 thru 421, article no. 112132, Elsevier, Oct 2026.
The definitive version is available at https://doi.org/10.1016/j.jms.2026.112132
Department(s)
Chemistry
Keywords and Phrases
1-ethyl-1-fluorosilacyclopentane; Conformational geometries; Kraitchman coordinates; Microwave spectroscopy; rS structure; Rotational spectroscopy
International Standard Serial Number (ISSN)
1096-083X; 0022-2852
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2026 Elsevier, All rights reserved.
Publication Date
01 Oct 2026
Comments
National Science Foundation, Grant CHE-MRI-2019072