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Direct Minimization Generating Electronic States with Proper Occupation Numbers

Kikuji Hirose·Tomoya Ono
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Abstract

We carry out the direct minimization of the energy functional proposed by Mauri, Galli and Car to derive the correct self-consistent ground state with fractional occupation numbers for a system degenerating at the Fermi level. As a consequence, this approach enables us to determine the electronic structure of metallic systems to a high degree of accuracy without the aid of level broadening of the Fermi-distribution function. The efficiency of the method is illustrated by calculating the ground-state energy of C$_2$ and Si$_2$ molecules and the W(110) surface to which a tungsten adatom is adsorbed.

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Kikuji Hirose, Tomoya Ono. 2000-10-04. Direct Minimization Generating Electronic States with Proper Occupation Numbers. https://doi.org/10.1103/physrevb.64.085105

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