Hirano Kenji, Nakano Hiroshi, Nakao Yoshihide, Sato Hirofumi, Sakaki Shigeyoshi
Department of Molecular Engineering, Kyoto University, Kyoto, 615-8510, Japan.
J Comput Chem. 2017 Jul 5;38(18):1567-1573. doi: 10.1002/jcc.24784. Epub 2017 Mar 27.
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.
通过具有空间电子密度分布的参考相互作用位点模型自洽场（RISM-SCF-SEDD）方法，研究了光活性黄色蛋白发色团对香豆酸在水溶液中的光吸收特性。RISM-SCF-SEDD是一种用于分子液体的电子结构理论和统计力学的组合方法。在此，将含时密度泛函理论与RISM方程相结合，以研究对香豆酸在水体系中的电子结构。计算了发色团在其中性、两种单阴离子和双阴离子形式下的激发能，以阐明去质子化和溶剂化对光谱性质的影响。我们发现，溶剂化强烈影响发色团的激发特性，特别是对于酚盐阴离子和双阴离子。还讨论了四种质子化状态之间的自由能差。©2017威利期刊公司。
