A FAST FULL-POTENTIAL LCAO METHOD FOR TOTAL-ENERGY MINIMIZATIONS

A new band structure method has been developed, specifically for the purpose of fast total-energy minimizations of large systems. Most characteristic of this linear combination of atomic orbitals (LCAO) method is that no position-dependent meshes for numerical integrations in real space are needed. All integrations that appear are done analytically, which makes the setting up of the secular matrix fast. Furthermore, with this LCAO method a number of new computational techniques are introduced, namely: (a) an efficient and simple solution of Poisson's and Schrodinger's equations for full potentials, (b) a new treatment of the non-linearity of the local-density approximation (LDA) exchange-correlation energy, and (c) an approximation technique for three-centre integrals.