An adaptive preconditioning scheme for the self-consistent field iteration and generalized stacking fault energy calculations

Abstract

The generalized stacking fault energy (GSFE) stands as a fundamental yet pivotal parameter for the plastic deformation of materials. In our investigation, we conduct first-principles calculations using the full-potential linearized augmented planewave (FLAPW) method to assess the GSFE, employing both single-shift and triple-shift supercell models. Different defects in these models result in different impacts on the self-consistent field (SCF) iterations and atomic relaxation. We propose an adaptive preconditioning scheme that can identify the long-wavelength divergence behavior of the Jacobian during the SCF iteration and automatically switch on the Kerker preconditioning to accelerate the convergence without any prior information. We implement this algorithm based on Elk-7.2.42 package and calculate the GSFE curves for the (111) plane along $〈\overline{1}\overline{1}2〉$ direction of Al, Cu, and Si. The results indicate that defects induced by the vacuum layer in the single-shift supercell model negatively impact the convergence of SCF iterations and atomic relaxation, therefore the triple-shift supercell model is more recommended.