Density functional theory for systems of very many atoms

The standard Kohn-Sham formulation of density functional theory (DFT ) is limited, for practical reasons, to systems of less than about 50-100 atoms. The computational effort scales as N, where N_at is the number of atoms and 2 < α > 3. (By comparison, conventional configuration interaction methods are limited to 5-10 atom systems.) This article deals with the prospect of practical methods that scale linearly in N_at and may thus allow calculations for systems of 10³-104 atoms. The physical reason (“near-sightedness”) for linear scaling is presented. Implementations of linear scaling DFT by the use of generalized Wannier functions or the one-particle density matrix are discussed. © 1995 John Wiley & Sons, Inc.