A spectral scheme for Kohn–Sham density functional theory of clusters

摘要: Starting from the observation that one of most successful methods for solving Kohn-Sham equations periodic systems - plane-wave method is a spectral based on eigenfunction expansion, we formulate designed towards clusters. This allows efficient calculation electronic structure clusters (and molecules) with high accuracy and systematic convergence properties without need any artificial periodicity. The basis functions in this form complete orthonormal set are expressible terms spherical harmonics Bessel functions. Computation occupied eigenstates discretized Hamiltonian carried out using combination preconditioned block eigensolvers Chebyshev polynomial filter accelerated subspace iterations. Several algorithmic computational aspects method, including computation electrostatics parallelization discussed. We have implemented these algorithms into an reliable package called ClusterES (Cluster Electronic Structure). A variety benchmark calculations employing local non-local pseudopotentials our results compared to literature. Convergence discussed through numerical examples. Computations involving large contain thousands electrons demonstrated highlight efficacy methodology. use study arbitrary point group symmetries briefly