describe in general terms the structure of ionic solids such as nacl
Ions typically pack into extremely regular crystalline structures, in an arrangement that minimizes the lattice energy.
Structure
Ions typically pack into extremely regular crystalline structures, in an arrangement that minimizes the lattice energy (maximizing attractions and minimizing repulsions). 
Ions typically pack into extremely regular crystalline structures, in an arrangement that minimizes the lattice energy The mineral is typically colorless or white, but may also be light blue, dark blue, purple, pink, red, orange, yellow or gray depending on inclusion of other materials, impurities, and structural or isotopic abnormalities in the crystals. Sodium and chloride
Ionic compound Halite Ionic compound
Structure Introduction Introduction
Ions typically pack into extremely regular crystalline structures, in an arrangement that minimizes the lattice energy The mineral is typically colorless or white, but may also be light blue, dark blue, purple, pink, red, orange, yellow or gray depending on inclusion of other materials, impurities, and structural or isotopic abnormalities in the crystals. These can be simple ions such as the sodium (Na) and chloride (Cl) in sodium chloride,
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Ionic compound [SEP] Structure
Ions typically pack into extremely regular crystalline structures, in an arrangement that minimizes the lattice energy (maximizing attractions and minimizing repulsions). The lattice energy is the summation of the interaction of all sites with all other sites. For unpolarizable spherical ions only the charges and distances are required to determine the electrostatic interaction energy. For any particular ideal crystal structure, all distances are geometrically related to the smallest internuclear distance. So for each possible crystal structure, the total electrostatic energy can be related to the electrostatic energy of unit charges at the nearest neighbour distance by a multiplicative constant called the Madelung constant that can be efficiently computed using an Ewald sum.