Fotofizica

Fotofizica is the scientific study of the physical processes that occur in matter when it absorbs electromagnetic radiation, particularly visible light. It is distinct from photochemistry, which focuses on the chemical reactions initiated by light. Fotofizica deals with the excited states of molecules and the transitions between these states, as well as the dissipation of energy from these excited states.

When a molecule absorbs a photon, it is promoted from its ground electronic state to an excited electronic state. This excited state is unstable and can undergo various processes. These include fluorescence, which is the emission of light from a singlet excited state, and phosphorescence, which is the emission of light from a triplet excited state. Other pathways for energy dissipation include internal conversion, where energy is lost as heat to the surroundings through vibrational relaxation, and intersystem crossing, a transition between singlet and triplet excited states.

Fotofizical phenomena are fundamental to a wide range of applications. They are central to understanding processes like vision, photosynthesis, and bioluminescence. In technology, fotofizica principles are crucial for the design of lasers, light-emitting diodes (LEDs), solar cells, and fluorescent probes used in microscopy and medical diagnostics. The study involves techniques such as absorption and emission spectroscopy, time-resolved spectroscopy, and quantum yield measurements to characterize the behavior of molecules in excited states.