摘要
本文首次研究了酸、碱及水等介质环境对HBO激发态质子转移(ESIPT)及其光谱的微扰.揭示了HBO^-、HBO^-的光谱特性.研究表明,在酸、碱化学环境下,HBO的ESIPT受到不同程度的阻碍;在多水环境下,HBO体系中存在稳定的基态HBO氢键单水合物而微扰质子转移,但少量的水,不产生明显的微扰;在375nm附近的吸收和430nm附近的发射应归属为HBO氢键单溶剂化物,而不是产生于构型Ⅲ的吸收和发射;氢键多溶剂化物是在质子性溶剂中产生正常荧光的主要物种.
In this paper,the environment perturbations of the excited state intramolecular proton transfer (ESIPT) and its spectra of 2-(2'-Hydroxyphenyl) benzoxazole (HBO) in the polar solvent doped impurities,such as acid, base and water,have been studied systematically. The spectral characteristics of protonated HBO+,deprotonated HBO- and some HBO-solvated in the solution systems perturbed are revealed and related to the properties of P-π conjugation of the hydroxyl O in HBO. ESIPT of HBO in the system perturbed is restricted to a considerable degree. In the system doped water with CH2o>1M,a new absorption band at 364nm and a new emission band at 432nm are found and ascribed to a stable HBO-monohydrate and an unstable HBO- * anion formed in the excited state, respectively. In protonic solution of HBO, a similar absorption at 375nm and emission at 432nm are thought to result from the H-bonding HBO-monosolvate and its HBO-* anion respectively,not from the rotamer Ⅲ of HBO.
基金
国家自然科学基金资助课题
