An ab initio study of water molecules in the bromide ion solvation shell

The solvation shell structure and dynamics of Br− in an aqueous solution of HBr (1.6 M) was studied, under ambient conditions, by ab initio molecular dynamics using the Car–Parrinello approach. The present calculations indicate that Br− is asymmetrically solvated by water. The calculated residence time of water in the inner Br− anion solvation shell agrees well with the most recent experimental estimate. Analysis indicates that the large anion scarcely influences the molecular dipole moment of solvation shell molecules.