Terahertz spectroscopy of dicyanobenzenes: Anomalous absorption intensities and spectral calculations

Date

2007-07-06

Author

Esentürk, Okan
Heilweil, E. J.

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Terahertz absorption spectra of three isomeric structures of dicyanobenzene in chloroform solution and solid phase at 298 K are reported. These spectra exhibit enhanced absorption in low THz range compared to most organic systems because of strong coupling to phonon modes. Molecular vibrational spectral calculations show strong correlation with the experiment especially for solution spectra. All intramolecular modes were assigned and intermolecular modes identified. Out-of-plane intramolecular modes at low frequency exhibit similar to 75 cm(-1) blue shifts as the secondary CN group moves from the para to ortho position on the benzene ring, whereas almost no frequency shift occurs for low-frequency in-plane modes.

Subject Keywords

Vibrational-Spectra, Raman

URI

https://hdl.handle.net/11511/45852

Journal

CHEMICAL PHYSICS LETTERS

DOI

https://doi.org/10.1016/j.cplett.2007.05.067

Collections

Department of Chemistry, Article

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Citation Formats

O. Esentürk and E. J. Heilweil, “Terahertz spectroscopy of dicyanobenzenes: Anomalous absorption intensities and spectral calculations,” CHEMICAL PHYSICS LETTERS, pp. 71–77, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/45852.