aDepartment of Chemistry, Faculty of Education and Welfare Science, Oita University, Dan-noharu 700, Oita 870-1192, Japan
bInstitute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
Abstract:
Hydration structure and dynamics of sodium chenodeoxycholate (CDC) in water are studied by a long-time molecular dynamics calculation. Strong hydration shell around the hydrophobic region of this large solute and strong hydrogen bonds of water with both hydroxyl and carboxyl oxygen atoms have been identified. The rotation of CDC around its longitudinal axis is found to be particularly active in comparison with that around other axes of the molecule. The diffusion coefficient of CDC calculated from the slope of the mean-square displacement, 0.95 × 10−9 m2/s, is only 1/6 of that for water in the solution, 5.4 × 10−9 m2/s.