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ION BOND

Ion bond is the interacting force between ions. The energy of the interaction of two ions and charges q1 and q2 is inversely proportional to the distance r between them and it is equal to

, where

ε - is electric permittivity of the medium,
ε0 - is electric permittivity of vacuum.
Similar charges repel and U > 0, unsimilar charges gravitate and U < 0.