Dissolved Salt

 We simulated how salt crystals dissolve in water.

In general, the forces acting between atoms is represented by a force(LJ) Lenard-Jones. Since the atom electrically neutral, do not feel the power from a distance. The mass attraction is not a zero, you can ignore it because it is much smaller than the electromagnetic force. When an atom close to the other atom, the electrons (negative charge) of the other atom will be distinguishable from the nucleus (positive charge). The atom detects the electric power, and it would begin to feel the Coulomb force. The LJ force model is a model to simulate the force model what is described above.

Soluble in water and salt decomposed into sodium and chlorine ions. The positive sodium, chlorinebecomes a negative ion, it is no longer electrically neutral even from a distance. Therefore, the ion is no longer electrically neutron, the Coulomb force must be taken into account between ions and water molecules. Each ions can not be applied the LJ model but the force model BMH-Tosi-Fumi.

Water molecules electrically polarized, so we can not apply the LJ force to water molecules. Usually the SPC / E model is used. These models, LJ, SPE, are proposed from empirically optima methods which has been proposed by various researchers. 

Place the salt water around the crystal. The temperature is set to be constant. 

The programming technique is reported and accepted in Journal of Computer Chemistry, Japan and the full paper is freely available from HERE.