Zharikov Anatoly A, Fischer Sighart F
Physik Department T-38, Technische Universität München, D-85748 Garching, Germany.
J Chem Phys. 2006 Feb 7;124(5):054506. doi: 10.1063/1.2165198.
The solvation of electrons in polar liquids is analyzed on the basis of an extended continuum model. In addition to the long-range electron-dipole interaction two short-range interactions are introduced. Among others one accounts for interactions with groups capable of forming hydrogen bonds and the second for quadrupolar characteristics of the liquid molecules. Both are induced by the orientation of the molecular dipole. Applying the scaling method a proper reaction coordinate is introduced and the solvation dynamics are discussed for the electron in the electronic ground state and after excitation to the p-type excited state. The observed spectral evolution of the transient absorption spectra, after two photon excitations for electrons in water and in methanol, is well described by this theory. An analytic estimate for the nonradiative deactivation from the electronically excited solvated electron is found to be consistent with an observed lifetime of 50 fs for the electron in water. The theory predicts an about three times slower internal conversion in methanol as solvent in comparison with water.
基于扩展连续介质模型对极性液体中电子的溶剂化进行了分析。除了长程电子 - 偶极相互作用外，还引入了两种短程相互作用。其中一种考虑了与能够形成氢键的基团的相互作用，另一种考虑了液体分子的四极特性。两者均由分子偶极的取向诱导。应用标度方法引入了合适的反应坐标，并讨论了处于电子基态以及激发到p型激发态的电子的溶剂化动力学。该理论很好地描述了在水和甲醇中对电子进行双光子激发后瞬态吸收光谱的观测光谱演化。发现对电子激发态溶剂化电子的非辐射失活的解析估计与在水中电子观测到的50飞秒寿命一致。该理论预测，与水作为溶剂相比，甲醇作为溶剂时内部转换速度慢约三倍。
