Central Research Institute for Physics, Atomic Energy Research Institute, P.O.B. 49, Budapest H-1525, Hungary.
J Chem Phys. 2011 Aug 28;135(8):084510. doi: 10.1063/1.3628677.
The photochemical yield of hydrated electrons as a function of temperature in liquid and supercritical water is treated in terms of energy fluctuations of the medium. The geminate pair, consisting of a positive ion and a hydrated electron, is regarded as a H-like atom embedded in a completely relaxed dielectric continuum. If the local medium energy is larger than the ionization energy of this atom, the electron escapes its geminate partner. By making use of the classical theory of energy fluctuations, escape probability is described by a simple explicit function, the variable of which is a combination of temperature, relative permittivity, and specific heat. First our earlier calculations on the recombination of solvated electrons, produced by ionizing radiation in a number of polar liquids, are improved and then the theory is compared with the experimental results on temperature dependent electron survival by Kratz et al. [S. Kratz, J. Torres-Alcan, J. Urbanek, J. Lindner, and P. Vöhringer, Phys. Chem. Chem. Phys. 12, 12169 (2010)]. Two adjustable parameters are needed to achieve reasonable quantitative agreement.
本文从介质能量波动的角度出发，研究了液态和超临界水中水合电子的光化学产率随温度的变化关系。由正离子和水合电子组成的成对电子被视为嵌入在完全弛豫介电连续体中的类 H 原子。如果局部介质能量大于该原子的电离能，则电子会逃离其配对伙伴。通过利用经典的能量波动理论，逃逸概率可以用一个简单的显式函数来描述，其变量是温度、相对介电常数和比热的组合。首先，我们改进了早期关于一系列极性液体中电离辐射产生的溶剂化电子复合的计算，然后将该理论与 Kratz 等人关于电子存活随温度变化的实验结果进行了比较[ S. Kratz, J. Torres-Alcan, J. Urbanek, J. Lindner, and P. Vöhringer, Phys. Chem. Chem. Phys. 12, 12169 (2010)]。需要两个可调参数才能达到合理的定量一致性。
