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Updated: Jun 24, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Ground- and excited-state tautomerization rates in porphycenes
P Fita1, N Urbańska, C Radzewicz
1Institute of Experimental Physics, University of Warsaw, Hoza 69, 00-681 Warsaw, Poland.
Abstract:
The rates of double hydrogen transfer in the ground and excited electronic states have been measured for porphycene and its derivatives by using a new method based on pump-probe polarization spectroscopy. Changing the strength of two intramolecular hydrogen bonds by altering the NHN distance leads to differences in the tautomerization rate exceeding three orders of magnitude. The reaction is considerably slower in the lowest electronically excited state. A correlation was found between the tautomerization rates and (1)H chemical shifts of the internal protons.
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