An arrangement of atoms commonly found in crystals containing oxygen, transition metal elements, and rare earth elements. A crystal is made up of MANY repetitions of this basic cubic structure.

Each type of atom has a different size: Oxygen atoms are the smallest, the transition metals ("B site") are medium sized, and the rare earths ("A site") are the largest. Chemical bonds are represented by bars connecting the atoms.

Crystals with this structure are studied by many physicists and engineers, including yours truly, for their strange electronic properties.