DESCRIPTION: Amide I mode vibrational spectra of four ideal secondary structural motiffs of peptides, R helix, 310 helix, parallel ? sheet, and antiparallel ? sheet, in response to three infrared pulses with wavevectors k1, k2, and k3 are simulated using a vibrational exciton model. Correlation plots of the signals generated at -k1 + k2 + k3 and +k1 + k2 - k3 show a characteristic peak pattern for each motiff. Resolution is enhanced by applying specific polarization configurations of the optical fields to oriented peptides.
REFERENCE: D. Abramavicius, W. Zhuang and S. Mukamel, "Peptide Secondary Structure Determination by Three-Pulse Coherent Vibrational Spectroscopies; A Simulation Study," J. Phys. Chem. B, 2004, 108, 18034-18045.