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arXiv · 0806.1723

Linear Augmented Slater-Type Orbital Method for Free Standing Clusters

K. S. Kang·J. W. Davenport·James Glimm·David Keyes·Michael McGuigan
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Abstract

We have developed a Scalable Linear Augmented Slater-Type Orbital (LASTO) method for electronic-structure calculations on free-standing atomic clusters. As with other linear methods we solve the Schrödinger equation using a mixed basis set consisting of numerical functions inside atom-centered spheres and matched onto tail functions outside. The tail functions are Slater-type orbitals, which are localized, exponentially decaying functions. To solve the Poisson equation between spheres, we use a finite difference method replacing the rapidly varying charge density inside the spheres with a smoothed density with the same multipole moments. We use multigrid techniques on the mesh, which yield the Coulomb potential on the spheres and in turn defines the potential inside via a Dirichlet problem. To solve the linear eigen-problem, we use ScaLAPACK, a well-developed package to solve large eigensystems with dense matrices. We have tested the method on small clusters of palladium.

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K. S. Kang, J. W. Davenport, James Glimm, David Keyes, Michael McGuigan. 2008-06-10. Linear Augmented Slater-Type Orbital Method for Free Standing Clusters. https://arxiv.org/abs/0806.1723

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