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Research Group Division of Earth and Planetary Materials Science


Mineral Research Group

•Assoc. Prof. Takahiro Kuribayashi,
specializing in Mineralogy and Crystallography. His research field is based on crystal structure analysis with single crystal X-ray diffraction method and infra-red absorption spectroscopy under high-pressure conditions.
•Assoc. Professor Toshiro Nagase (The Tohoku University Museum),
specializing in Mineralogy and Crystallography. His research field is based on analysis of texture and structure of minerals with electron microscope.


This group has several classes related to Mineralogy, Crystallography and Crystal Chemistry.
Students will be able to learn several techniques to make characterizations and evaluations on minerals with various methods such as X-ray and electron diffraction methods, scanning and transmission electron microscopy (SEM and TEM) observation, spectroscopy (Visible, IR, Raman) and so on.

(1) Crystal structures of minerals under special conditions such as high pressure and high temperature conditions:

Crystal structure of a material controls its various physical properties such as compressibility, thermal conductivity and so on. Especially, under special conditions such as high-p and high-T conditions, crystal structure is to change and physical properties of the material should be changed. Lots of physical properties are affected by correlation between electrons of each atom in its crystal structure. Therefore, the electron density distributions in crystal structure are most important information to understand physical properties of minerals. The best way to know the electron density distributions is to analyze its crystal structure in detail using single crystal X-ray diffraction methods using a synchrotron facilities (PF, KEK, Tsukuba, Japan).

(2) The behavior of hydrogen bonding in hydrous minerals under high-pressure and high-temperature conditions:

Dense hydrous magnesium silicate minerals are stable under high PT conditions like deep Earth interior. They have hydrogen bond in their structures and hydrogen bond affects on its stability under these conditions because of its speciality. Most important information to understand the behavior of hydrogen bond is location of hydrogen in its crystal structure under special conditions. However, the estimation of hydrogen position in crystal is so difficult experimentally. Now we are trying to make estimations of hydrogen positions in crystal structure under high-pressure conditions using Maximum Entropy (ME) analysis with a single crystal X-ray diffraction data set. Also, now our group is taking part in the special big academic project (2008-2013) entitled "Neutron Earth Science" (http://yagi.issp.u-tokyo.ac.jp/shingakujutsu/en/index.html).

(3) Texture of Minerals:

3) Texture of Minerals: Minerals show various textures in the crystal. The textures include information about history of minerals; transition, crystal growth, and deformation etc. We observe fine-texture and micro-structure of minerals by using TEM and SEM, to reveal the history of minerals.