Using density functional theory (DFT) and time-dependent DFT quantum-chemical methodologies, we investigate interplay of electronic properties and conformational dynamics in several optically active materials. In quantum dots we explore the role of surface ligands on the electronic structure and observe strong surface-ligand interactions leading to formation of hybridized states and polarization effects. This opens new relaxation channels for high energy photoexcitations. Computations of Ru(II)-bipyridine attached to the semiconductor quantum dot systems demonstrate possibility of charge separation and energy transfer processes in the complex. In the amorphous clusters of conjugated polymers, we find that electron trap states are induced primarily by intra-molecular configuration disorder, while the hole trap states are generated primarily from inter-molecular electronic interactions. All these phenomena govern experimentally observed photoinduced dynamics and define technologically important properties of materials suitable for solar energy conversion.