KSSOLV 2.0: An efficient MATLAB toolbox for solving the Kohn-Sham equations with plane-wave basis set

KSSOLV (Kohn-Sham Solver) is a MATLAB toolbox for performing Kohn-Sham density functional theory (DFT) calculations with a plane-wave basis set. KSSOLV 2.0 preserves the design features of the original KSSOLV software to allow users and developers to easily set up a problem and perform ground-state calculations as well as to prototype and test new algorithms. Furthermore, it includes new functionalities such as new iterative diagonalization algorithms, k-point sampling for electron band structures, geometry optimization and advanced algorithms for performing DFT calculations with local, semi-local, and hybrid exchange-correlation functionals. It can be used to study the electronic structures of both molecules and solids. We describe these new capabilities in this work through a few use cases. We also demonstrate the numerical accuracy and computational efficiency of KSSOLV on a variety of examples. Program title: Kohn-Sham Solver 2.0 (KSSOLV 2.0) CPC Library link to program files:https://doi.org/10.17632/pp8vgvfcv4.1 Developer's repository link:https://bitbucket.org/berkeleylab/kssolv2.0/src/release/ Licensing provisions: BSD 3-clause Programming language:: MATLAB Nature of problem: KSSOLV2.0 is used to perform Kohn-Sham density functional theory based electronic structure calculations to study chemical and material properties of molecules and solids. The key problem to be solved is a constrained energy minimization problem, which can also be formulated as a nonlinear eigenvalue problem. Solution method: The KSSOLV 2.0 implements both the self-consistent field (SCF) iteration with a variety of acceleration strategies and a direct constrained minimization algorithms. It is written completely in MATLAB and uses MATLAB's object oriented programming features to make it easy to use and modify.