Ionisation
Definition
Removal of an electron from a specified atom or molecule. The required energy depends on the target; photon energy alone does not describe every radiation effect. Wave descriptions account for interference, diffraction and polarisation, while photon energy helps describe quantised interactions.
- Context
- Electromagnetic radiation
For example, the energy needed to remove an electron depends on the target; a UV band name alone does not establish that interaction.
Energy per photon is not total exposure or biological harm.
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