car-parrinello molecular dynamics simulations of na+-cl- ion pair in liquid water
;J.M.Khalack;A.P.Lyubartsev
conference on human factors in computing systems - proceedings2004Vol. 7pp. 683-698
240
j.m.khalack2004condensedcar-parrinello
Abstract
The aqueous solvation shell of a Na+-Cl- pair is studied using Car-Parrinello molecular dynamics simulations. Water-mediated and contact states of the ion pair are investigated. The first hydration shell of the Na+ ion is found to be octahedral with one vacant position for both states. In the contact state one of the water molecules is substituted by the Cl- ion. The first hydration shell of the Cl- is less structured and strongly effected by the proximity of the Na+ in the contact state. The oxygen coordination numbers for Na+ and Cl- are 4.9 and 5.6 for the water-mediated state, and 3.6 and 6.4 for the contact state. The corresponding hydrogen coordination numbers are 10.9 and 5.2; 9.2 and 3.9, respectively.