Analytic atomic gradients in the fermi‐löwdin orbital self‐interaction correction.

We derived, implemented, and thoroughly tested the complete analytic expression for atomic forces, consisting of the Hellmann‐Feynman term and the Pulay correction, for the Fermi‐Löwdin orbital self‐interaction correction (FLO‐SIC) method. Analytic forces are shown to be numerically accurate through an extensive comparison to forces obtained from finite differences. Using the analytic forces, equilibrium structures for a small set of molecules were obtained. This work opens the possibility of routine self‐interaction free geometrical relaxations of molecules using the FLO‐SIC method. © 2018 Wiley Periodicals, Inc. Analytic atomic forces in molecular systems and solids are an essential tool for today's electronic structure calculations. The authors derive the expression and implement the analytic forces for the Fermi‐Löwdin orbital self‐interaction correction (FLO‐SIC) method within density functional theory (DFT). This development allows feasible geometrical relaxations with self‐interaction free DFT. [ABSTRACT FROM AUTHOR]