同位素取代液态水的三维红外光谱揭示了非均相动力学。

Three-dimensional infrared spectroscopy of isotope-substituted liquid water reveals heterogeneous dynamics.

机构信息

Institute of Physical Chemistry, University of Zurich, Zurich, Switzerland.

出版信息

J Phys Chem B. 2011 Jun 2;115(21):6976-84. doi: 10.1021/jp201989s. Epub 2011 May 11.

DOI:10.1021/jp201989s

Abstract

The dynamics of the hydrogen bond network of isotopically substituted liquid water are investigated with a new ultrafast nonlinear vibrational spectroscopy, three-dimensional infrared spectroscopy (3D-IR). The 3D-IR spectroscopy is sensitive to three-point frequency fluctuation correlation functions, and the measurements reveal heterogeneous structural relaxation dynamics. We interpret these results as subensembles of water which do not interconvert on a half picosecond time scale. We connect the experimental results to molecular dynamics (MD) simulations, performing a line shape analysis as well as complex network analysis.

摘要

本文利用一种新的超快非线性振动光谱技术——三维红外光谱（3D-IR）研究了同位素取代液态水中氢键网络的动力学。3D-IR 光谱对三点频率波动相关函数敏感，测量结果揭示了非均相结构弛豫动力学。我们将这些结果解释为在半皮秒时间尺度上不相互转化的水亚群。我们将实验结果与分子动力学（MD）模拟联系起来，进行了谱线形状分析和复杂网络分析。