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Vibrational excitons, resonant energy transfer, and local structure in liquid benzene
Journal of Chemical Physics (1977)
  • Richard Alan Lesar
  • R. Kopelman
The presence of vibrational excitons in liquid benzene has been tested by the method of isotopic dilution. A C6H6/C6D6 concentration study on the infrared and Raman fundamental modes reveals that the umbrella (A 2u ) vibrational exciton in solid benzene retains its characteristics upon melting and at room temperature. The total liquidexciton bandwidth is about 40 cm−1, practically the same as in the solid. This indicates an instantaneous local liquid structure similar to that of the solid (the C i crystal site symmetry is also nearly preserved), in general agreement with indications from other methods. The fastest nearest neighbor vibrational resonant transfer takes about 1 psec. The residual linewidth at isotopic dilution is 3–4 cm−1, which is due to inhomogeneous and/or homogeneous broadening. The respective overall reorientational and/or translational relaxation takes about 2 psec o r l o n g e r. The excitonlinewidth is proportional to the square root of the isotopic concentration except for a sudden break at some critical concentration.
  • excitons,
  • linewidths,
  • liquid structure,
  • vibration resonance,
  • crystalline solids
Publication Date
June 1, 1977
Publisher Statement
Copyright 1977 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
Citation Information
Richard Alan Lesar and R. Kopelman. "Vibrational excitons, resonant energy transfer, and local structure in liquid benzene" Journal of Chemical Physics Vol. 66 Iss. 11 (1977)
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