Vibrational energy redistribution and vibrational dynamics of methanol mixed with Rhodamine 101 dye

Vibrational energy transfer that occurs after photoexcitation can be tracked in the first several femtoseconds by ultrafast time- and frequency-resolved CARS (coherent anti-Stokes Raman scattering) spectroscopy. Vibrational energy transfer from high-frequency modes to lower ones through chemical bond of pure methanol and methanol/Rhodamine 101 (Rh101) solution is detected. Through comparison and analysis of the experimental results, it is found that surrounding molecules have a significant influence on vibrational energy transfer and vibrational couplings among relevant modes.