The Existence of dense ferroelectric ice under high pressure

高圧下における誘電氷の構造解明

関根 由莉奈   ; 深澤 裕; 荒川 雅*; 阿部 淳; 服部 高典   ; 佐野 亜沙美   ; 内海 渉; 有馬 寛*; 上床 美也; 小松 一生*; 鍵 裕之

Sekine, Yurina; Fukazawa, Hiroshi; Arakawa, Masashi*; Abe, Jun; Hattori, Takanori; Sano, Asami; Utsumi, Wataru; Arima, Hiroshi*; Uwatoko, Yoshiya; Komatsu, Kazuki*; Kagi, Hiroyuki

The existence of a ferroelectric ice, named ice XI, at atmospheric pressure have been predicted; however it is not clear whether other ferroelectric ices exist or not under high pressure, because of a difficulty of in-situ high-pressure neutron experiment. We first measured neutron diffraction of powder ice crystal under 1.4 GPa and 60 K. From a new developed high-pressure cell for an intense pulsed-neutron beam, we observed that the diffraction profile has a peak at 0.206 nm, which is consistent with a ferroelectric ice, predicted by simulation studies. Any peak of antiferroelectric ice is not observed. This result suggests that the dense ferroelectric ice is a low temperature structure of ice VI. The dense ferroelectric ice exists in an interior of cool icy body. The ice, possessing the ability to storage an electric charge, could have had important effects on electric and physical properties of cool planets and satellites.