Is the reason behind the vibrating the movement of electrons from a stable to a excited state? My quest for knowledge began with this question..."How exactly does light transform into heat--for instance, when sunlight warms up a brick wall? I understand that electrons in the atoms in the wall absorb the light, but how does that absorbed sunlight turn into thermal energy?" I later found out that the atoms are perpetually vibrating due to the resonance of the solar energy. Soon enough, the vibration causes atoms to collide and heat. But, how does light cause the vibration of the atoms?