2013 Fiscal Year Final Research Report

Elucidation of the behavior of hydrogen and hydroxyl ions based on the hydrogen-bond network analysis

Research Project

Project/Area Number	24654082
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Single-year Grants
Research Field	Condensed matter physics I
Research Institution	Tohoku University
Principal Investigator	AKAGI Kazuto 東北大学, 原子分子材料科学高等研究機構, 准教授 (50313119)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	水 / 水素結合ネットワーク / 水素イオン / 水酸化物イオン / 環状構造 / 第一原理計算 / 計算機シミュレーション
Research Abstract	Elucidation of the rule which determines the behavior or spatial distribution of hydronium and hydroxyl ions in aqueous solutions will lead to the way of understanding or controlling of various catalytic reactions. In this project, systematic analyses of the hydrogen-bond network, which consists of weak bonds among water molecules, were done focusing on the "ring structures" included in it, and two important findings were obtained as follows: (1) Liquid water involves the microscopic inhomogeneity caused by these "ring structures", and (2) Hydronium and hydroxyl ions feel repulsive interaction from a certain kind of "ring structure". These concepts are based on the results from computer simulations, but it was also implied that they are relatively independent from the accuracy of how to model the atoms and molecules.