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Title: Infrared Spectroscopy of the Tropyl Radical in Helium Droplets

Abstract

Here, the infrared spectrum of the $$\tilde{X}$$ 2E 2" tropyl radical has been recorded in the range of the CH-stretch vibrational modes using the helium droplet isolation technique. Two bands are observed at 3053 and 3058 cm –1. The electronic degeneracy of the ground state results in a Jahn–Teller interaction for two of the CH-stretch modes, i.e., first-order interaction for E 3' symmetry modes and second-order interaction for E 2' symmetry modes. The experimentally observed bands are assigned to the E 1' and E 3' CH-stretch modes. The E 1' mode is infrared-active, whereas the E 3' mode is inactive in the absence of the Jahn–Teller interaction. The transition to the upper component of the Jahn–Teller split E 3' mode gains intensity via vibronic coupling, giving rise to the second experimentally observed band.

Authors:
 [1];  [1];  [1];  [2]; ORCiD logo [2]
  1. Ruhr-Univ. Bochum, Bochum (Germany)
  2. Univ. of Georgia, Athens, GA (United States)
Publication Date:
Research Org.:
Univ. of Georgia Research Foundation, Athens, GA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1409059
Grant/Contract Number:
SC0008086
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory
Additional Journal Information:
Journal Volume: 120; Journal Issue: 34; Journal ID: ISSN 1089-5639
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Kaufmann, Matin, Leicht, Daniel, Havenith, Martina, Broderick, Bernadette M., and Douberly, Gary E.. Infrared Spectroscopy of the Tropyl Radical in Helium Droplets. United States: N. p., 2016. Web. doi:10.1021/acs.jpca.6b06522.
Kaufmann, Matin, Leicht, Daniel, Havenith, Martina, Broderick, Bernadette M., & Douberly, Gary E.. Infrared Spectroscopy of the Tropyl Radical in Helium Droplets. United States. doi:10.1021/acs.jpca.6b06522.
Kaufmann, Matin, Leicht, Daniel, Havenith, Martina, Broderick, Bernadette M., and Douberly, Gary E.. 2016. "Infrared Spectroscopy of the Tropyl Radical in Helium Droplets". United States. doi:10.1021/acs.jpca.6b06522. https://www.osti.gov/servlets/purl/1409059.
@article{osti_1409059,
title = {Infrared Spectroscopy of the Tropyl Radical in Helium Droplets},
author = {Kaufmann, Matin and Leicht, Daniel and Havenith, Martina and Broderick, Bernadette M. and Douberly, Gary E.},
abstractNote = {Here, the infrared spectrum of the $\tilde{X}$2E2" tropyl radical has been recorded in the range of the CH-stretch vibrational modes using the helium droplet isolation technique. Two bands are observed at 3053 and 3058 cm–1. The electronic degeneracy of the ground state results in a Jahn–Teller interaction for two of the CH-stretch modes, i.e., first-order interaction for E3' symmetry modes and second-order interaction for E2' symmetry modes. The experimentally observed bands are assigned to the E1' and E3' CH-stretch modes. The E1' mode is infrared-active, whereas the E3' mode is inactive in the absence of the Jahn–Teller interaction. The transition to the upper component of the Jahn–Teller split E3' mode gains intensity via vibronic coupling, giving rise to the second experimentally observed band.},
doi = {10.1021/acs.jpca.6b06522},
journal = {Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory},
number = 34,
volume = 120,
place = {United States},
year = 2016,
month = 8
}

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