Issue 24, 2017

Fermi resonance as a means to determine the hydrogen-bonding status of two infrared probes

Abstract

The C[double bond, length as m-dash]O/C[triple bond, length as m-dash]N stretching vibration arising from a carbonyl/nitrile functional group in various molecular systems has been frequently used to assess, for example, local hydrogen-bonding interactions, among other applications. However, in practice it is not always easy to ascertain whether the carbonyl or nitrile group in question is engaged in such interactions. Herein, we use 4-cyanoindole and cyclopentanone as models to show that, when a fundamental C[double bond, length as m-dash]O or C[triple bond, length as m-dash]N stretching mode is involved in Fermi resonance, the underlying vibrational coupling constant (W) is a convenient reporter of the hydrogen-bonding status of the corresponding carbonyl or nitrile group. Specifically, we find that for both groups a W value of 7.7 cm−1 or greater is indicative of their involvement in hydrogen-bonding interactions. Furthermore, we find that, as observed in similar studies, the Fermi resonance coupling leads to quantum beats in the two-dimensional infrared spectra of 4-cyanoindole in isopropanol, with a period of about 1.9 ps.

Graphical abstract: Fermi resonance as a means to determine the hydrogen-bonding status of two infrared probes

Supplementary files

Article information

Article type
Paper
Submitted
14 Apr 2017
Accepted
04 Jun 2017
First published
05 Jun 2017

Phys. Chem. Chem. Phys., 2017,19, 16144-16150

Fermi resonance as a means to determine the hydrogen-bonding status of two infrared probes

J. M. Rodgers, R. M. Abaskharon, B. Ding, J. Chen, W. Zhang and F. Gai, Phys. Chem. Chem. Phys., 2017, 19, 16144 DOI: 10.1039/C7CP02442H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements