"ionic bonding" is a kind of chemical bonding that arises from the mutual attraction of oppositely charged ions. ions of like charge repel each other, and ions of opposite charge attract each other. therefore, ions do not usually exist on their own, but will bind with ions of opposite charge to form a crystal lattice. the resulting compound is called an "ionic compound", and is said to be held together by "ionic bonding". in ionic compounds there arise characteristic distances between ion neighbours from which the spatial extension and the ionic radius of individual ions may be derived.