Temperature dependence and non-Condon effects in pump–probe spectroscopy in the condensed phase

We analyze the effects of the coordinate dependence of the transition dipole (non-Condon dipole moment) on impulsive pump–probe spectroscopy at finite temperatures, using expressions for the response functions derived by the path-integral approach. We calculate the difference probe absorption spectrum and show that the non-Condon dipole shifts the absorption to the blue and that the shift increases with temperature.