Term: two-photon photochromism
https://doi.org/10.1351/goldbook.TT07491

Definition:
Photochromic process involving a two-photon process. The process might involve the simultaneous or the sequential absorption of two photons.

Related Terms:
1) two-photon process (http://doi.org/10.1351/goldbook.T06542).

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 436 (https://doi.org/10.1351/pac200779030293)

Citation: 'two-photon photochromism' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.TT07491

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