Complete determination of relaxation parameters from two-dimensional Raman spectroscopy

Using the model of a weakly-anharmonic, underdamped oscillator coupled to a bath, we demonstrate that the 2D time-resolved Raman signal carries information about the population decay T-1, the homogeneous dephasing T-2, and the inhomogeneous dephasing T-1 relaxation timescales. We distinguish between two projections of the 2D signal. first, the echo signal, which is stretched in the diagonal direction decays with T-2. and the second which is stretched along one a?;is is related to the population relaxation and decays with T-1. The width of both signals reflects T-1. Equations of motion for vibrational coherence and population variables are employed in these calculations.