Excited-State Intramolecular Proton Transfer: A Short Introductory Review

Area of Science:

• Photochemistry
• Physical Chemistry
• Spectroscopy

Background:

• Excited-state intramolecular proton transfer (ESIPT) is a fundamental photophysical process.
• First observed by Weller in salicylic acid derivatives, ESIPT has garnered significant research interest.
• ESIPT plays a crucial role in various applications, driving further investigation into its properties.

Purpose of the Study:

• To review and elucidate the multifaceted aspects of ESIPT.
• To provide a mechanistic perspective on ESIPT and tautomerization.
• To consolidate current understanding of ESIPT phenomena and their influencing factors.

Main Methods:

• Literature review of available studies on ESIPT.
• Analysis of mechanistic viewpoints regarding ESIPT and tautomerization.
• Discussion of factors affecting ESIPT, such as excitation wavelength and hydrogen bonding.

Main Results:

• Detailed examination of ESIPT mechanisms, including excitation wavelength dependence and anti-Kasha pathways.
• Exploration of the kinetics of ESIPT, distinguishing between fast and slow processes.
• Investigation into the reversibility, irreversibility, and geometrical influences on ESIPT, as well as excited-state double proton transfer (ESDPT) mechanisms.

Conclusions:

• ESIPT is a complex phenomenon with diverse mechanistic pathways.
• Understanding ESIPT is critical for its application in various scientific fields.
• Further research into ESIPT and ESDPT will continue to expand its utility.