2013 Fiscal Year Final Research Report

Diffusion dynamics of hydrogen molecules in clathrate hydrate

Research Project

Project/Area Number	24740198
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Condensed matter physics I
Research Institution	The University of Tokyo
Principal Investigator	KOFU Maiko 東京大学, 物性研究所, 助教 (70549568)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	水素 / 包接化合物 / 中性子散乱
Research Abstract	The relaxation dynamics of the H2 molecules in the clathrate hydrate has been investigated by using quasielastic neutron scattering (QENS) techniques. New type of samples cell were developed for high-pressure measurements. We have found that the H2 molecules move in the timescale of 10ps between 180K and 210K. By investigating how the relaxation changes with the scattering vector, it is made clear that the relaxation is of local origin. On the other hand, no relaxation was detected in the timescale between 0.1ns and 2ns at the temperature ranging from 5K to 260K. To understand what happens, we are now planning to investigate the relaxation of the H2 molecules between 10ps and 0.1ns. These measurements can reveal the motion of the H2 molecules in the clathrate hydrate.