title: Spin currents and spin dynamics in time-dependent density-functional theory.
abstract: We derive and analyze the equation of motion for the spin degrees of freedom within time-dependent spin-density-functional theory (TD-SDFT). The 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.
authors.affiliation: Departamento de Química e Física Molecular, Instituto de Química de São Carlos, Universidade de São Paulo, Caixa Postal 780, São Carlos SP, 13560-970 Brazil.
authors.forename: K
authors.initials: K
authors.lastname: Capelle
authors.forename: G
authors.initials: G
authors.lastname: Vignale
authors.forename: B L
authors.initials: BL
authors.lastname: Györffy