Anharmonic coupling between fundamental modes in tetramethylurea
Date of Issue2014
School of Materials Science and Engineering
In situ high pressure Raman spectra of tetramethylurea have been measured up to 25 GPa, liquid-solid and solid-solid phase transitions were detected at 0.2 GPa and 7.4 GPa, respectively. An unprecedented spectral phenomenon is the observation of a Fermi resonance between the fundamental modes. An exponential relationship between the intensity and the frequency difference was concluded. Pressure provides us a new way to study the correlation between Fermi resonance parameters.
The journal of chemical physics
© 2014 AIP Publishing LLC. This paper was published in The Journal of Chemical Physics and is made available as an electronic reprint (preprint) with permission of AIP Publishing LLC. The paper can be found at the following official DOI: http://dx.doi.org/10.1063/1.4872159. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.