Accuracy control in ultra-large-scale electronic structure calculations

Abstract

Numerical aspects are investigated in ultra-large-scale electronic structure calculations.Accuracy control methods in process (molecular-dynamics) calculations are focusedupon. Flexible control methods are proposed so as to control variational freedoms,automatically at each time step, within the framework of generalized Wannierstate theory. The method is demonstrated in a silicon cleavage simulation with102–105 atoms. The idea is of general importance among process calculations and is alsoused in Krylov subspace theory, which is another large-scale calculation theory.