Relation between dielectric and low-frequency Raman spectra of hydrogen-bond liquids.
We analyzed the complex dielectric and Raman spectra of hydrogen-bond liquids in the microwave to terahertz frequency range. As for water and methanol, the high-frequency component of the dielectric spectrum, i.e., the small deviation from the principal Debye relaxation, clearly corresponds to the Raman spectrum. This indicates that the cooperative relaxation, accompanied by huge polarization fluctuation, is virtually not Raman active, whereas the faster processes reflect common microscopic dynamics. For ethylene glycol, the shape of the Raman spectrum also resembles that of the high-frequency deviation of the dielectric spectrum, but, additionally, a weak manifestation of the cooperative relaxation arising from quadrupolar conformers is detected.
Fukasawa
Toshiko
T
Advanced Research Institute for Science and Engineering, Waseda University, Okubo 3-4-1, Shinjuku-ku, Tokyo 169-8555, Japan.
Sato
Takaaki
T
Watanabe
Junji
J
Hama
Yoshimasa
Y
Kunz
Werner
W
Buchner
Richard
R