Franck–Condon amplitude for two-photon processes within a displaced harmonic model
Takayuki Omae, Kisaburo Deguchi · The Journal of Chemical Physics · 1982
An alternate expression of Franck-Condon amplitude is derived which does not contain the infinite summation over the vibrational states given below: Imn = 𝒥∞v = 0(<χgm‖χev≳ <χev‖χgn≳)/(ωr+Egn− Eev). The new Imn is given below: Imn = (Nm/2π) (Nn/2π) ℱ2π0 dϑdϑ′ eimϑeimϑe−inϑ′ e−sA𝒥∞v (av/v!) (b−cv)−1. (AIP)