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Spin currents and spin dynamics in time-dependent density-functional theory

K. Capelle·G. Vignale·B. L. Gyorffy
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Abstract

We derive and analyse the equation of motion for the spin degrees of freedom within time-dependent spin-density-functional theory (TD-SDFT). Results are (i) a prescription for obtaining many-body corrections to the single-particle spin currents from the Kohn-Sham equation of TD-SDFT, (ii) the existence of an exchange-correlation (xc) torque within TD-SDFT, (iii) a prescription for calculating, from TD-SDFT, the torque exerted by spin currents on the spin magnetization, (iv) a novel exact constraint on approximate xc functionals, and (v) the discovery of serious deficiencies of popular approximations to TD-SDFT when applied to spin dynamics.

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K. Capelle, G. Vignale, B. L. Gyorffy. 2001-10-01. Spin currents and spin dynamics in time-dependent density-functional theory. https://doi.org/10.1103/physrevlett.87.206403

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