Occurs when an atom or molecule and their concomitant ions have energy states whereby the energy in two or more photons is absorbed.
Source: PAC, 1991, 63, 1541. (Recommendations for nomenclature and symbolism for mass spectroscopy (including an appendix of terms used in vacuum technology). (Recommendations 1991)) on page 1548 [Terms] [Paper]
Citation: 'multiphoton ionization' in IUPAC Compendium of Chemical Terminology, 3rd ed. International Union of Pure and Applied Chemistry; 2006. Online version 3.0.1, 2019. https://doi.org/10.1351/goldbook.M04053 RISBibTexEndNote