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Krylov Subspace Method for Molecular Dynamics Simulation based on Large-Scale Electronic Structure Theory

Ryu Takayama·Takeo Hoshi·Takeo Fujiwara
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Abstract

For large scale electronic structure calculation, the Krylov subspace method is introduced to calculate the one-body density matrix instead of the eigenstates of given Hamiltonian. This method provides an efficient way to extract the essential character of the Hamiltonian within a limited number of basis set. Its validation is confirmed by the convergence property of the density matrix within the subspace. The following quantities are calculated; energy, force, density of states, and energy spectrum. Molecular dynamics simulation of Si(001) surface reconstruction is examined as an example, and the results reproduce the mechanism of asymmetric surface dimer.

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Ryu Takayama, Takeo Hoshi, Takeo Fujiwara. 2004-03-19. Krylov Subspace Method for Molecular Dynamics Simulation based on Large-Scale Electronic Structure Theory. https://doi.org/10.1143/jpsj.73.1519

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