Photolysis

Photolysis is the chemical breakdown of a substance after it absorbs light. The absorbed energy can break chemical bonds or initiate reactions that produce new substances.

Photon: A photon is a quantum of electromagnetic radiation that carries energy and momentum. A photolysis event begins when a molecule absorbs a photon's energy.
Electromagnetic spectrum: The electromagnetic spectrum is the full range of electromagnetic radiation, ordered by frequency or wavelength. Photolysis depends on the radiation wavelengths available to the reacting substance.
Ozone–oxygen cycle: The ozone–oxygen cycle is the stratospheric sequence of reactions that forms and destroys ozone and molecular oxygen. Ultraviolet photolysis of oxygen and ozone drives key steps in this cycle.
Oxygen photodissociation: Oxygen photodissociation is the breakup of molecular oxygen into oxygen atoms by absorbed ultraviolet radiation. This atmospheric example supplies oxygen atoms that can form ozone.
Photochemical reaction: A photochemical reaction is a chemical transformation initiated by the absorption of light. Photolysis is one pathway within the broader class of light-initiated chemical transformations.
Absorption spectroscopy: Absorption spectroscopy measures how strongly a substance absorbs radiation across wavelengths. Absorption spectra identify wavelengths capable of initiating photolysis.
Atmospheric photochemistry: Atmospheric photochemistry studies chemical reactions initiated by sunlight in Earth's atmosphere. Photolysis supplies reactive species that govern many atmospheric reaction chains.
Ozone photodissociation: Ozone photodissociation is the breakup of an ozone molecule after absorbing ultraviolet radiation. Its products help regulate ultraviolet radiation and stratospheric chemistry.
Photodissociation: Photodissociation is the breakup of a molecule into smaller species after it absorbs a photon. This is the direct bond-cleavage pathway often meant by photolysis.
Electronic excitation: Electronic excitation is the promotion of an electron to a higher-energy state after energy absorption. Absorption commonly places a photolysing molecule in a reactive excited state.

Linked from 19 pages