白雲母および方解石/水界面の構造と物性(<特集>水が関係する結晶成長のトピックス)

抄録

Mineral/water interfaces control ion substitution, dissolution, precipitation, and crystal growth. Atomic-scale structure of mineral/water interfaces is important for understanding the interaction among mineral surface, water, dissolved ions and molecules. The interfacial structures have been revealed by surface X-ray scattering measurements by comparing the results with molecular simulations. In this review, we explain the methods and interpretation of the X-ray scattering profiles and molecular simulations applied for muscovite and calcite/water interfaces. Different hydration structures of K^+ and Cs^+ on a muscovite surface is revealed by the method. Wettability alteration of a calcite surface is discussed based on a molecular simulation. We show the results that ion substitution of the outermost layer of the calcite surface can be stable, though the incorporation of the foreign ions in bulk crystal is unstable. These results should be important for understanding various phenomena occurring at the crystal surface during the growth.