Water Dynamics; Fluctuation and Chemical Reactions

水动力学；

基本信息

批准号：
14001001
负责人：
OHMINE Iwao
金额：
$ 188.03万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Specially Promoted Research
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2005
项目状态：
已结题

项目摘要

We have addresses following five issues in " water dynamics and its diversity "(1) Hydrogen bond network rearrangement dynamics at normal and low temperatures ; There are two liquid states in low temperature water; low - density liquids (LDL) and high - density liquids (HDL). We have made a fragment analysis to find the nature of their hydrogen bond network structures. It is found that most of LDL space is covered with only 15 types of basic fragments. Also found is that there exists the very strong structural constrains among the fragments; only a couple type fragments can attach to a given fragment. This fact explains the reason why the phase transition can exist between LDL and HDL. We have also showed how frequency-dependent heat capacity changes in the super-cooled state with temperature, and revealed its relationship of dynamics and 3D - response function of polarizability.(2) Molecular mechanism for the crystallization and melting of water ; We have analyzed the formation of an … More initial nucleus and nucleation process in water freezing process by using fragment analysis. A similar analysis is applied for the melting process of ice.(3) Theoretical analysis of non-linear multi-dimensional spectroscopy, especially 2D - Raman Spectroscopy; We have made a new theoretical analysis on 2D- Raman Spectroscopy in order to find the nature of the low-frequency motions of liquids. It is found that this method is very sensitive to the nonlinearity of dynamics so that can be applied to detect the regularity of a structure; for example, it can detect the detail mechanism of how the very small ice structure is being built and grows in the process of water freezing.(4) Hydration structure of ions; We have made a calculation to estimate the auto-dissociation constant of water molecule and temperature dependence theoretically, and succeeded to reproduce its temperature dependence almost completely and obtain the hydration structure of the ions. From the analysis, we have found the detail mechanism of the hydration structure and the interaction, and how the long-range electron transfer takes place in this hydration process. Also found is that, when temperature rises, the stability of all energy of ionic dissociation ncreases. (This opposite to the common knowledge.) We found the physio-chemical reason for it. This finding is related to the high reactivity of supercritical water. Now, we have been investigating about hydration structure of ions near the surfaces of liquids.(5) Reaction dynamics of proteins (biological polymer) ; Light cycle of Photoactive Yellow Proton (PYP) and the ion transport membranes; We have investigate the overall structural change of PYP and the ionic transport mechanism in a ion channel model system. Less

我们在“水动力学及其多样性”（1）在正常和低温下的氢键网络重新排列动力学中有五个问题。低温水中有两个液态。低密度液体（LDL）和高密度液体（HDL）。我们进行了片段分析，以找到其氢键网络结构的性质。发现大多数LDL空间仅覆盖了15种基本片段。还发现，碎片之间存在非常强大的结构缺陷。只有几个类型的片段可以连接到给定的片段。这个事实解释了LDL和HDL之间可以存在相变的原因。我们还展示了频率依赖性的热容量如何随温度冷却状态变化，并揭示了其动力学与极化性的3D响应功能的关系。（2）水结晶和熔化水的分子机制；我们已经通过使用碎片分析分析了在水冷冻过程中形成……更多的初始核和核过程。（3）非线性多维光谱，尤其是2D-RAMAN光谱法的理论分析也采用了类似的分析。我们已经对2D拉曼光谱法进行了新的理论分析，以找到液体低频运动的性质。发现该方法对动力学的非线性非常敏感，因此可以应用于结构的规律性。例如，它可以检测到如何在水冷冻过程中建造非常小的冰结构并生长的细节机制。（4）离子的水合结构；我们进行了计算，以估计水分子和温度依赖理论的自动分解常数，并成功地几乎完全重现其温度依赖性并获得离子的水合结构。从分析中，我们发现了水合结构和相互作用的详细机理，以及在此水合过程中如何进行远距离电子转移。还发现，当温度升高时，是离子解离生长的所有能量的稳定性。（这与常识相反。）我们发现了它的理化原因。这一发现与超临界水的高反应性有关。现在，我们一直在研究液体表面附近离子的水合结构。（5）蛋白质的反应动力学（生物聚合物）；光活性黄质子（PYP）和离子传输机制的光周期；我们已经研究了离子通道模型系统中PYP和离子传输机制的总体结构变化。较少的