Structure and stability of iron oxide surfaces and their reactivity with water

Energy minimisation and molecular dynamics were used to investigate the structure and stability of a range of hematite, Fe₂O₃, surfaces. The Born model of solids was used to describe the forces between atoms. One of the novel features of this work is that molecular dynamics simulations are used to obtain the phonon density of states from which we can calculate the size of the contribution of the zero point energy and vibrational entropy to the free energy of both point defects and interfaces. This work has focused on the [0001 and {1012} surfaces. Examination of the surfaces reveals that there are a number of possible configurations and that the zero point energy contribution is a significant component of the surface free energy. The results reported here also suggest that the surfaces interact strongly with water.