Theoretical calculations of infrared absorption, vibrational circular dichroism, and two-dimensional vibrational spectra of acetylproline in liquids water and chloroform

The vibrational circular dichroism, infrared absorption and two-dimensional vibrational spectra of acetylproline in liquids water and chloroform were studied. Quantum chemistry calculations and molecular dynamics simulations were carried out for the study. The Frenkel exciton model was used to describe one- and two-exciton states of the dipeptide, acetylproline in solutions. Correlation between ensemble averaged conformations of the acetylproline molecule in liquids water and chloroform was analyzed. It was observed that in liquids water and chloroform, the corresponding conformations of acetylproline were close to the ideal 3₁₀ helix and the C ₇ structure, respectively.