Figure 2.

Examples of excited-state molecular motions leading to different nonradiative pathways including (A) S₁–S₀ vibronic coupling (adapted with permission from Ref. [3], Copyright Royal Society of Chemistry), (B) conical intersection (adapted with permission from Ref. [5,6], Copyright Royal Society of Chemistry and Ref. [7], Copyright, American Chemical Society), (C) dark state (adapted with permission from Ref. [8,9], Copyright Wiley-VCH and Ref. [10], Copyright ChemRxiv) and (D) photochemical reaction (adapted with permission from Ref. [11,12], Copyright American Chemical Society; further permissions related to Ref. [12] should be related to the American Chemical Society). CI = conical intersection, PET = photoinduced electron transfer, TICT = twisted intramolecular charge transfer, ISC = intersystem crossing.