What is relation between interatomic potential and interatomic distance?

 The interatomic potential describes the interaction between a pair of atoms or the interaction of an atom with a group of atoms in a condensed phase. The potential must have both an attractive and a repulsive component if binding is to occur. The form of the potential energy as a function of lattice spacing (interatomic distance, r) in a solid is illustrated. Each atom in the ideal crystalline solid experiences the same potential due to the other atoms in the material.

The binding energy of the atom in the solid is the depth of the potential well at its minimum. The location of this minimum determines the nearest neighbor distance, r0 , for atoms in the solid.