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DOE OSTI · 22499147

Efficient two-component relativistic method for large systems

Nakai, Hiromi
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Abstract

This paper reviews a series of theoretical studies to develop efficient two-component (2c) relativistic method for large systems by the author’s group. The basic theory is the infinite-order Douglas-Kroll-Hess (IODKH) method for many-electron Dirac-Coulomb Hamiltonian. The local unitary transformation (LUT) scheme can effectively produce the 2c relativistic Hamiltonian, and the divide-and-conquer (DC) method can achieve linear-scaling of Hartree-Fock and electron correlation methods. The frozen core potential (FCP) theoretically connects model potential calculations with the all-electron ones. The accompanying coordinate expansion with a transfer recurrence relation (ACE-TRR) scheme accelerates the computations of electron repulsion integrals with high angular momenta and long contractions.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSANGULAR MOMENTUMDIRAC OPERATORSELECTRON CORRELATIONELECTRONSHAMILTONIANSHARTREE-FOCK METHODINTEGRALSPOTENTIALSRELATIVISTIC RANGESCALING

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Nakai, Hiromi. 2015-12-31. Efficient two-component relativistic method for large systems. https://doi.org/10.1063/1.4938838

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