fotonionizáció

Fotonionizáció, also known as photoionization, is a physical process where an atom, molecule, or ion absorbs one or more photons and loses one or more electrons. This occurs when the energy of the absorbed photons exceeds the ionization energy of the species. In simpler terms, light with sufficient energy can knock an electron out of an atom or molecule.

The probability of photon ionization depends on factors such as the photon energy, the electronic structure of the atom or molecule, and the target species itself. For many elements, ultraviolet or X-ray photons are required to cause ionization due to the relatively high ionization energies. However, for highly excited atoms or molecules, even visible light can be energetic enough to trigger this process.

Photon ionization is a fundamental process in various scientific fields. It plays a role in atmospheric chemistry, astrophysics, and in many experimental techniques like mass spectrometry and photoelectron spectroscopy. In these applications, the interaction of light with matter is used to study the composition and properties of substances, or to understand physical phenomena occurring in extreme environments like stars. The process can occur in a single-photon event, where one photon provides all the necessary energy, or in multi-photon ionization, where multiple photons are absorbed to achieve ionization.