氢键(O:H-O)受激弛豫势能路径的键弛豫理论与声子谱学实验标定

Water is the source and an important part of all lives. However, water performs anomalously under excitation compared with other normal substance. Developing new theories and detection techniques has been a great challenge. Our recent progress [Huang et al., Coord Chem Rev 2015, 285: 109-165] indicates that the coupling of the hydrogen bond (O:H-O) short-range interactions with Coulomb repulsion between electron pairs on adjacent oxygen ions dictates the anomalies of water and ice. Determination of the asymmetric, local, short-range interaction is however beyond the scope of the currently available theoretical and experimental approaches. The objective aims to resolving this problem by combining our original strategies of hydrogen bond cooperativity theory, Lagrangian oscillating dynamics, and phonon spectrometrics, and the experience in mapping the potential paths for the hydrogen bond relaxing under compression. The novelty and breakthrough of this project lie in the theoretical, numerical and experimental strategies to map the potential paths of hydrogen bond relaxation under thermal excitation and molecular undercoordination. Developed strategies and completion of this project will provide important impact to resolving the mysteries of water and ice that has been the dream of many scientists.

水是一切生命的起源和重要组成部分。但是水的所有可测物性皆反常。建立新的理论体系和研究方法是探解水之谜的关键所在。我们的研究进展(Huang et al., Coord Chem Rev 2015, 285: 109-165)表明，氢键(O:H-O)的O:H和H-O各自分段相互作用与O-O的电子对间库伦排斥的耦合导致氢键的受激协同弛豫决定水的反常物性。但是，现有理论和试验方法对测定氢键的短程、局域、非对称作用势这一基本物理力学参量却无能为力。此项课题旨在利用我们提出的“氢键耦合双振子模型”与拉格朗日力学和声子计量谱学的组合，在前期研究基础上探讨在受热和受限条件下氢键长度和能量的弛豫。主要突破点在于通过理论预测、实验标定、解析计算将实验测得的氢键分段长度和振动频率转换为相应的力常数和键能，得到氢键受激弛豫的势能路径。从而充实我们的氢键理论体系及相应的检测技术和数值计算方法，以破解水的更多谜底。

水是一切生命的起源和重要组成部分。但是水的所有可测物性皆反常。建立新的理论体系和研究方法是探解水之谜的关键所在。本项目基于“氢键耦合双振子模型”，结合拉格朗日力学和声子计量谱学，通过采集水在变温和受限条件下的拉曼声子谱，发展拉曼差分声子谱方法进行谱学分析，获取氢键受激时的声子弛豫信息，并将实验测得的氢键分段长度和振动频率转换为相应的力常数和键能，构建了氢键受激弛豫的势能路径。结果进一步证实了氢键非对称耦合双振子模型及库仑调制氢键非对称弛豫机制的正确性，也证实了受激诱导的氢键分段局域短程作用的协同弛豫主导着水乃至水溶液的诸多物性。这将有效充实我们的氢键理论体系及相应的检测分析技术，以破解水的更多谜底。