Center for Molecular Spectroscopy and Dynamics

Summary:

To theoretically describe 2D IR spectroscopy, which elucidates molecular structure and dynamics, we need to calculate the third order vibrational response function. The present research aims to calculate this response function in the classical limit by way of molecular dynamics (MD) simulation employing quantum mechanical/molecular mechanical (QM/MM) force field. In this approach, important characteristics of molecular systems, such as potential anharmonicity, spectral diffusion, chemical exchange, and vibrational energy relaxation are naturally reflected in the calculated spectrum without further theoretical modeling. Moreover, the spectrum spans the entire molecular vibrational frequency range, revealing correlations between disparate vibrational modes.

One eye-catching figure

:Calculated 2D IR spectrum of the three intramolecular modes of HOD in a hydrated HOD system