What structural units make up iconic solids?

Iconic solids are primarily composed of ions arranged in a regular, repeating three-dimensional lattice structure. These solids are formed when cations and anions attract each other due to electrostatic forces, resulting in a stable configuration. The arrangement of these ions maximizes attraction while minimizing repulsion, leading to characteristic properties such as high melting points and electrical conductivity when dissolved in water or molten. Examples of iconic solids include sodium chloride (NaCl) and magnesium oxide (MgO).