How to draw the lattice and crystal lattice structure of ionic compounds?

It is difficult to draw the lattice structures of without a computer.

It is more important that you be able to recognize the unit cells in the lattice structures.

The positive and negative ions are often in a cubic array. Here are two examples.

##"CsCl"##, a simple cubic structure

The ##"Cl"^-## ions are the blue atoms at the corners of the cube.

The ##"Cs"^+## ions are at the centre of the cube.

The unit cell extends through the whole crystal.

This animation shows the ##"CsCl"## lattice, the ##"Cs"## sublattice in blue, and the ##"Cl"## sublattice in brown.

##"NaCl"##, a face centred cube

The green ##"Cl"^-## ions occupy each corner and the centre of each face of the cube.

In the picture below, the ##"Na"^+## ions also occupy a face-centred cubic unit cell.

These unit cells extend through the whole crystal.