Formation and energy of the ionic bonds

Metal atoms have strong properties to lose electrons and become cations.
On the contrary, non-metallic atoms have strong properties to obtain electrons and become anions.
As these two particles approach each other, electrons move between the two particles. Eventually, both particles become cations and anions with a stable electron configuration.

There are two forces between cations and anions:

  • Attractive force: Electrostatic attraction is applied between cation and anion.
  • Repulsive force: When two ions approach very close, a strong repulsive force acts between the electron clouds.

How determined the distance of ionic bond?

The most suitable distance for ionic bonding is the lowest energy combined with attractive force and repulsive force. This distance is the ion binding distance.