caa a22 4500 463217039 CHVBK 20180405153200.0 cr unu---uuuuu 170326e20070101xx s 000 0 eng 10.1007/s00269-006-0126-6 doi (NATIONALLICENCE)springer-10.1007/s00269-006-0126-6 Raman spectra of methane hydrate up to 86GPa [Elektronische Daten] [Shin-Ichi Machida, Hisako Hirai, Taro Kawamura, Yoshitaka Yamamoto, Takehiko Yagi] High-pressure Raman studies of methane hydrate were performed using a diamond anvil cell in the pressure range of 0.1-86GPa at room temperature. Raman spectra of the methane molecules revealed that new softened intramolecular vibration mode of ν 1 appeared at 17GPa and that the splitting of vibration mode of ν 3 occurred at 15GPa. The appearance of these two modes indicates that an intermolecular attractive interaction increases between the methane molecules and the host water molecules and between the neighboring methane molecules. These interactions might result in the exceptional stability of a high-pressure structure, a filled ice Ih structure (FIIhS) for methane hydrate, up to 40GPa. At 40GPa, a clear change in the slope of the Raman shift versus pressure occurred, and above 40GPa the Raman shift of the vibration modes increased monotonously up to 86GPa. A previous XRD study showed that the FIIhS transformed into another new high-pressure structure at 40GPa. The change in the Raman spectra at 40GPa may be induced by the transition of the structure. Springer-Verlag, 2006 Methane hydrate nationallicence High pressure nationallicence Raman spectroscopy nationallicence Intermolecular interaction nationallicence DAC nationallicence Machida Shin-Ichi Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, Ibaraki, Japan aut Hirai Hisako Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, Ibaraki, Japan aut Kawamura Taro National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8569, Ibaraki, Japan aut Yamamoto Yoshitaka National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8569, Ibaraki, Japan aut Yagi Takehiko Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581, Chiba, Japan aut Physics and Chemistry of Minerals Springer-Verlag 34/1(2007-01-01), 31-35 0342-1791 34:1<31 2007 34 269 https://doi.org/10.1007/s00269-006-0126-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00269-006-0126-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Machida Shin-Ichi Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, Ibaraki, Japan aut NATIONALLICENCE 700 1- Hirai Hisako Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, 305-8572, Ibaraki, Japan aut NATIONALLICENCE 700 1- Kawamura Taro National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8569, Ibaraki, Japan aut NATIONALLICENCE 700 1- Yamamoto Yoshitaka National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8569, Ibaraki, Japan aut NATIONALLICENCE 700 1- Yagi Takehiko Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581, Chiba, Japan aut NATIONALLICENCE 773 0- Physics and Chemistry of Minerals Springer-Verlag 34/1(2007-01-01), 31-35 0342-1791 34:1<31 2007 34 269 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer