Ultrafast relaxation dynamics of solvated electrons in water

被引：57

作者：

Hertwig, A ^{[1
]}

Hippler, H ^{[1
]}

Unterreiner, AN ^{[1
]}

Vohringer, P ^{[1
]}

机构：

[1] Univ Karlsruhe, Inst Phys Chem & Elektrochem, Lehrstuhl Mol Phys Chem, D-76128 Karlsruhe, Germany

来源：

BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 1998年 / 102卷 / 06期

关键词：

chemical kinetics; liquids; solvated electrons; spectroscopy; ultrafast;

D O I：

10.1002/bbpc.19981020603

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The relaxation dynamics of excess electrons in a water jet between 5 and 70 degrees C have been investigated on an ultrashort timescale. We have probed the transient absorption of the system immediately after UV multiphoton-ionization with a 266 nm ultrashort laser pulse and a time resolution of about 50 fs. Probe wavelengths ranging from 450 to 1000 nm have been provided by a generated white-light continuum. The data suggest a superposition of geminate recombination of the solvated electrons with their original counter-ions and of relaxation into thermal equilibrium. Relaxation into thermal equilibrium is the much faster process and is completed after about 6 ps while the geminate recombination is much slower, temperature independent, and prevails for at least 100 ps. The here postulated interpretation of the data clearly shows that no other transient states than "hot solvated electrons" are required for an understanding of the observed ultrafast dynamics within our time resolution.

引用

页码：805 / 810

页数：6

共 31 条

[1] Electronic absorption spectra of size-selected hydrated electron clusters: (H2O)(n)(-), n=6-50 [J].