Comparative ab initio calculation studies of hydration structures on Cs and other alkaline metals

Machida, Masahiko; Sakuramoto, Kazuhiro*; Okumura, Masahiko; Nakamura, Hiroki; Sato, Yuya*; Akutsu, Keiko*; Shiga, Motoyuki

no journal, , 

We report the results of ab initio molecular dynamics simulation on the hydration structure of monovalent Cs cation, which is one of the most fundamental issues in terms of chemical forms of Cs. The ion hydration of heavy alkali species, Rb and Cs, have been not studied thoroughly as Na and K. Using the VASP code, ab initio molecular dynamics are performed to examine and compare the hydrated structures of monovalent Li, Na, K, Rb, and Cs ions. It is found that hydrated Rb and Cs ions constitute very flexible solvation shells. Moreover, we also investigate the dynamical properties, such as the residence time of water molecules in the first shell. Consequently, we find that the exchange rate of water molecules of the first shell in Cs is significantly fast compared to other ion cases.