The purpose of the present work is to focus on some of those methods, discussing their performance, their limitations and their advantages, by applying them to the simulation of the photoisomerization process of a retinal chromophore model including the effect of an environment of growing complexity . The model Hamiltonian of the system represents the photo-induced 11-cis to all-trans isomerization of retinal in rhodopsin (a simplified, and wellestablished, precursor of the model studied in Ref. ) using two electronic states and two effective nuclear modes. The effect of the environment is accounted for by including secondary Raman-active modes represented by a bath of harmonic oscillators coupled to the electronic states.