Japan Geoscience Union Meeting 2018

Presentation information

[EJ] Oral

M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS07] Interface- and nano-phenomena on crystal growth and dissolution

Wed. May 23, 2018 10:45 AM - 12:15 PM A03 (Tokyo Bay Makuhari Hall)

convener:Yuki Kimura(Institute of Low Temperature Science, Hokkaido University), Hitoshi Miura(Graduate School of Natural Sciences, Department of Information and Basic Science, Nagoya City University), Katsuo Tsukamoto(大阪大学大学院工学研究科, 共同), Hisao Satoh(Naka Energy Research Laboratory, Mitsubishi Materials Corporation), Chairperson:Kimura Yuki(Institute of Low Temperature Science, Hokkaido University)

10:45 AM - 11:00 AM

[MIS07-01] Molecular-level understanding of ice crystal surfaces by advanced optical microscopy

*Ken Nagashima1, Gen Sazaki1, Ken-ichiro Murata1, Yoshinori Furukawa1 (1.The Institute of Low Temperature Science, Hokkaido University)

Keywords:Ice, Surface melting, Quasi-liquid layer, Molecular step

Ice is one of the most abundant crystals on the earth, and hence the molecular-level understanding of ice crystal surfaces holds the key to unlocking the secrets of a number of fields. We and Olympus Engineering Co., Ltd. have developed laser confocal microscopy combined with differential interference contrast microscopy (LCM-DIM), by which we succeeded in the direct visualization of 0.37-nm-thick elementary steps [1] on ice for the first time with enough spatial and temporal resolution. Subsequently, the direct observations of spiral steps on ice basal faces revealed the double-spiral-step structure [2], the migration distance of water molecules adsorbed on a terrace [3], and the temperature dependence of the step kinetic coefficient [4].
On the other hand, we could also visualize the quasi-liquid layers (QLLs) on ice crystal surfaces [5], which are covered with thin liquid layers even below the melting point (0°C). The direct observations of QLLs revealed the appearance of two types of QLLs with different morphologies [5,6], the appearance temperatures and partial pressure of water vapor [6-8], the inducement of the formation of QLLs by strain [9], and the characteristic velocities of QLLs [10]. Further details of QLLs will be presented in "A-CC28: Glaciology" sessions.
In addition, we also found that atmospheric acidic gas (hydrogen chloride gas) strongly induced the appearances of droplets on ice surfaces (further details will be presented in "A-AS06: Atmospheric Chemistry" session). The droplets were observed in the temperature range of -15.0 ~ -1.5°C, where no QLL appears in the absence of HCl gas [11]. The HCl induced droplets were embedded into ice crystals by growth of ice crystals [12]. These results show the possibility that ice crystals can store large amount of gas components as fluid inclusions.
[1] Sazaki et al. (2010) PNAS 107, 19702.
[2] Sazaki et al. (2014) Cryst. Growth Des. 14, 2133.
[3] Asakawa et al. (2014) Cryst. Growth Des. 14, 3210.
[4] Inomata et al. (2018) Cryst. Growth Des. 18, 786.
[5] Sazaki et al. (2012) PNAS 109, 1052.
[6] Murata et al. (2016) PNAS 113, E6741.
[7] Asakawa et al. (2015) Cryst. Growth Des. 15, 3339.
[8] Asakawa et al. (2015) PNAS 113, 1749.
[9] Sazaki et al. (2013) Cryst. Growth Des. 13, 1761.
[10] Murata et al. (2015) Phys. Rev. Lett. 115, 256103.
[11] Nagashima et al. (2016) Cryst. Growth Des. 16, 2225.
[12] Nagashima et al., submitted.