title: Effect of chemical substitutions on photo-switching properties of 3-hydroxy-picolinic acid studied by ab initio methods.
abstract: Effect of chemical substitutions to the molecular structure of 3-hydroxy-picolinic acid on photo-switching properties of the system operating on excited-state intramolecular double proton transfer (d-ESIPT) process [M. F. Rode and A. L. Sobolewski, Chem. Phys. 409, 41 (2012)] was studied with the aid of electronic structure theory methods. It was shown that simultaneous application of electron-donating and electron-withdrawing substitutions at certain positions of the molecular frame increases the height of the S0-state tautomerization barrier (ensuring thermal stability of isomers) and facilitates a barrierless access to the S1/S0 conical intersection from the Franck-Condon region of the S1 potential-energy surface. Results of study point to the conclusion that the most challenging issue for practical design of a fast molecular photoswitch based on d-ESIPT phenomenon are to ensure a selectivity of optical excitation of a given tautomeric form of the system.
authors.affiliation: Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland.
authors.forename: Michał F
authors.initials: MF
authors.lastname: Rode
authors.affiliation: Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland.
authors.forename: Andrzej L
authors.initials: AL
authors.lastname: Sobolewski