Moreover, the possibility of building consistent FFs for GS and ES paves the way to detailed descriptions of excited state dynamics. In this section, we resort to the parameterization of the GS and ES FFs both at the ground and the first excited state of dithiophene, already reported in a previous work by some of us, and here re-performed with the JOYCE3.0 code. Furthermore, in the case of the ES, we considered two different minima (cis and trans configurations around the central bond), each with a dedicated FF. As shown in the original publication, the usual analyses on the quality of the FF reveal a similar accuracy for both GS and ES, compared to the reference data at DFT and TDDFT levels, respectively, confirming that the method is able to provide consistent parameterizations at both states. The CEA-VE calculation of the emission spectra, averaged for both cis and trans configurations, along with the one for absorption, are shown in Figure (green dashed lines). Even applying a phenomenological Gaussian broadening with HWHM = 0.05 to each transition, the comparison with the experiments reveals a considerable underestimation of the overall width for absorption and emission. This is, however, an expected effect, as the conformation ensemble arising from a classical sampling generally underestimates the spectral width, especially when the role of progressions along high-frequency modes is significant. One way to address a proper simulation of the spectra, which considers the quantum nature of the high-frequency modes, while retaining an extended CL sampling for both the soft modes of the solute and those of the environment, consists in adopting a MQC strategy, as the Ad-MD|gVH method, recently proposed by some of us. As discussed in the Methods Section, in this strategy the flexible degrees of freedom of the solute (specifically the torsion between the two thiophene rings) and the solvent are treated classically, while the stiff modes of the solute are treated at QM level. The electronic structure calculations carried out at each configuration extracted along the MD trajectory are usually performed at DFT and TDDFT levels for both states, which renders the Ad-MD|gVH protocol computationally demanding.