ヤマモト　ノリフミ   Norifumi Yamamoto   山本　典史    所属   千葉工業大学  工学部 応用化学科    千葉工業大学  工学研究科 工学専攻    千葉工業大学  工学研究科 応用化学専攻    職種   教授
言語種別	日本語
発行・発表の年月	2012
形態種別	学術雑誌
査読	査読あり
標題	Excited-state intramolecular proton transfer and charge transfer in 2-(2'-hydroxyphenyl)benzimidazole crystals studied by polymorphs-selected electronic spectroscopy
執筆形態	共著
掲載誌名	Physical Chemistry Chemical Physics
巻・号・頁	14,16448-16457頁
著者・共著者	Hayato Konoshima, Saori Nagao, Issui Kiyota, Kiichi Amimoto, Norifumi Yamamoto, Masahiko Sekine, Munetaka Nakata, Kazuki Furukawa and Hiroshi Sekiya
概要	Crystal structures of polymorphs of 2-(2'-hydroxyphenyl)benzimidazole (HPBI), Forms α and β, are analyzed by X-ray crystallography. The fluorescence excitation (FE) and fluorescence spectra of the polymorphs are separately observed at temperatures 77–298 K. It has been found that the electronic spectra of the two crystal forms are significantly different from each other. Photo-excitation of the enol forms in Forms α and β induces the excited-state intramolecular proton transfer (ESIPT) to produce the S1 state of the keto forms. In the FE spectra of Forms α and β, the S1 ← S0 (ππ*) transition of the keto form is observed in the 360–420 nm region in addition to that of the enol form in the 250–420 nm region. In the FE spectrum of Form β a new band peaking at 305 nm is observed, which is assigned to the S1 ← S0 transition of a non-planar enol form based on the observation of dual fluorescence in the UV and visible regions and