Time-delayed infrared-visible probe pulses in five-wave mixing spectroscopy

While a number of pumped sum-frequency experiments have been done to study the dynamics occurring at surfaces and interfaces, all these experiments involve coincident infrared-visible probe pulses. Here, we analyze the possibilities of using time-delayed infrared-visible probe pulses in five-wave mixing spectroscopy to study the dynamical processes which take place in the higher vibrational molecular levels. To this end, we introduce in the present work a general analytical description of time-delayed infrared-visible probe pulses to test the influence of the physical parameters driving the internal dynamics of the molecular adsorbate on the five-wave mixing signal. Two different configurations have been considered with the infrared probe beam resonant with either the first or the second vibrational transition showing different sentivities to the dephasing processes acting on the upper vibrational states.