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arXiv · 0707.2704

Determination of the Mott insulating transition by the multi-reference density functional theory

K. Kusakabe
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Abstract

It is shown that a momentum-boost technique applied to the extended Kohn-Sham scheme enables the computational determination of the Mott insulating transition. Self-consistent solutions are given for correlated electron systems by the first-principles calculation defined by the multi-reference density functional theory, in which the effective short-range interaction can be determined by the fluctuation reference method. An extension of the Harriman construction is made for the twisted boundary condition in order to define the momentum-boost technique in the first-principles manner. For an effectively half-filled-band system, the momentum-boost method tells that the period of a metallic ground state by the LDA calculation is shortened to the least period of the insulating phase, indicating occurrence of the Mott insulating transition.

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K. Kusakabe. 2007-07-18. Determination of the Mott insulating transition by the multi-reference density functional theory. https://doi.org/10.1088/0953-8984%2F19%2F36%2F365229

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