Effects of proline ring conformation on theoretical π‐π* absorption and CD spectra of helical poly(L‐proline) forms I and II

Absorption and CD spectra of the π‐π* transition near 200 nm are calculated for helical (Pro)10 forms I and II with a variable proline ring conformation characterized by torsion angle χ2 in the range −60° to 60°. The spectra for poly (Pro) I are not sufficiently sensitive to χ2 to suggest a preferred ring conformation. The spectra for poly (Pro) II are more sensitive to χ2, and suggest preferred ring conformations near either or both of the χ2regions −50 ± 10° and 50 ± 10°.

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