ANYL 19 |
| CW THz spectroscopy has been used to obtain spectra from 2 cm-1 to 100 cm-1 of several tripeptides and a number of dipeptide nanotubes, at 4.2 K. For the crystalline tripeptides ala-ala-ala, ala-gly-ala, and gly-ala-gly, quite different spectra are found. In addition, two forms of anti-parallel beta sheet trialanine, differing only in the presence or absence of water crosslinking the sheets, share no common spectral features despite the weakness of the interactions with water. The mid-IR region, in contrast, is insensitive to these changes. In a second series of studies, two families of crystalline dipeptides that have similar hydrogen bonding networks and crystal structures, were investigated. Unlike the tripeptides, these spectra show similarities within families, indicating the importance of hydrogen bonding to Thz spectra. These experimental results provide insight into the nature and scope of hydrogen bonding force fields necessary to model the structure and spectra of these simple peptides. |
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General Papers
8:30 AM-11:35 AM, Sunday, 28 August 2005 Washington DC Convention Center -- 155, Oral
Sci-Mix
Division of Analytical Chemistry |