Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.
Invitrogen

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 26 July 1996:
Vol. 273. no. 5274, pp. 480 - 483
DOI: 10.1126/science.273.5274.480
Prev | Table of Contents | Next

Reports

Low-Frequency Raman Scattering and the Fast Relaxation Process in Glycerol

Takashi Uchino * and Toshinobu Yoko

Ab initio molecular orbital calculations were used to determine the structure and vibrational frequencies of the cyclic glycerol trimer, which represents the region of medium-range ordering in liquid and supercooled glycerol. The calculations reproduced the experimentally observed low-frequency Raman scattering peak (or the "boson peak") at sim 50 per centimeter, which suggests that the peak results from the localized collective motions of the cooperatively hydrogen-bonded hydroxyl groups. The calculations also suggest that the fast relaxation process may result from the translational motion of each glycerol molecule in the cyclic structure. On the basis of these results, a model of the glass transition was developed.

Institute for Chemical Research, Kyoto University, Uji, Kyoto 611, Japan.
*   To whom correspondence should be addressed.




ADVERTISEMENT
Click Me!

ADVERTISEMENT
Click Me!

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)