The simulation of general polar boundaries

We show that there is a general method for quenching the macroscopic dipole that is found when a stack of planes is set up along a polar direction. We therefore show how simulations of these polar interfaces can be performed. We also show that there is a category of polar interface that cannot be st abilised in any simple way that both quenches the dipole and is chemically reasonable. We illustrate the method by calculating the energies of a numbe r of boundaries in spinel. (C) 1999 Elsevier Science B.V. All rights reserv ed.