title: Photo absorption of p-coumaric acid in aqueous solution: RISM-SCF-SEDD theory approach.
abstract: Photo absorption properties of p-coumaric acid, the chromophore of photoactive yellow protein, in aqueous solution were investigated by means of reference interaction site model self-consistent field with spatial electron density distribution (RISM-SCF-SEDD) method. RISM-SCF-SEDD is a combination methodology of electronic structure theory and statistical mechanics for molecular liquids. Here, time-dependent density functional theory was coupled with RISM equation to study the electronic structure of p-coumaric acid in aqueous system. Excitation energies of the chromophore in its neutral, two monoanionic and dianionic forms were computed to elucidate the effect of the deprotonation and solvation on the spectroscopic properties. We found that solvation strongly affects the excitation character of the chromophore, especially for phenolate anion and dianion. The free energy difference among the four protonation states is also discussed. © 2017 Wiley Periodicals, Inc.
authors.affiliation: Department of Molecular Engineering, Kyoto University, Kyoto, 615-8510, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Hirano
authors.affiliation: Department of Molecular Engineering, Kyoto University, Kyoto, 615-8510, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakano
authors.affiliation: Department of Molecular Engineering, Kyoto University, Kyoto, 615-8510, Japan.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Nakao
authors.affiliation: Department of Molecular Engineering, Kyoto University, Kyoto, 615-8510, Japan.
authors.forename: Hirofumi
authors.identifier: 0000-0001-6266-9058
authors.initials: H
authors.lastname: Sato
authors.affiliation: Department of Molecular Engineering, Kyoto University, Kyoto, 615-8510, Japan.
authors.forename: Shigeyoshi
authors.initials: S
authors.lastname: Sakaki
keywords: RISM-SCF-SEDD; pCA; photoactive yellow protein; solvation effect