Torsional vibrational modes of tryptophan studied by terahertz time-domain spectroscopy.
نویسندگان
چکیده
The low-frequency torsional modes, index of refraction, and absorption of a tryptophan film and pressed powders from 0.2 to 2.0 THz (6.6-66 cm(-1)) were measured by terahertz time-domain spectroscopy at room temperature. It was found that there were two dominated torsional vibrational modes at around 1.435 and 1.842 THz. The associated relaxation lifetimes ( approximately 1 ps) for these modes of the tryptophan molecule were measured. Using a density-functional calculation, the origins of the observed torsional vibrations were assigned to the chain and ring of the tryptophan molecule.
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ورودعنوان ژورنال:
- Biophysical journal
دوره 86 3 شماره
صفحات -
تاریخ انتشار 2004