MD simulation of KCl, KBr and KI salts in water at 298.15 K

A. Ujjankar, S. H. Ganatra and

Abstract

The molecular dynamic simulation of K+ + Cl- + H2O, K+ + Br- + H2O and K+ + I- +H2O systems were carried at 298.15K. It is reported that in case of K+ + Br- +H2O system shows higher aggregation as compared to the K+ + Cl- + H2O which may be due to the higher ionic radii and atomic weight of Br- ions. K+ + Cl- + H2O system provide higher degree of interaction with solute-solute interaction as compared with K+ + Br- + H2O and K+ + I- +H2O. It is concluded that system having smaller ions like Cl-, the orientation of water molecules indicates dominance of electrostatic mechanism, whereas in case of Br- ions surrounding water, it may be due electrostatic orientation and water–water hydrogen-bonding ordering mechanism of water molecules. In case of I- anions, which is larger in size, the water molecule orientation may be due to electrostatic tendency to orient dipole with respect to ion and hydrogen-bonding tendency to orient adjacent water molecules as shown by Barbara Hribar in their study.