Article,
Magnetic susceptibility, exchange interactions and spin-wave spectra in the local spin density approximation
Journal of Physics: Condensed Matter, 16 (41): 7439-7446 (2004)
Abstract
Starting from an exact expression for the dynamical spin susceptibility
in the time-dependent density functional theory, a controversial
issue regarding exchange interaction parameters and spin-wave excitation
spectra of itinerant electron ferromagnets is reconsidered. It is
shown that the original expressions for exchange integrals based
on the magnetic force theorem (Liechtenstein et al 1984 J.~Phys.~F:~Met.~Phys.
14 ~L125) are optimal for calculations of the magnon spectrum, whereas
the static response function is better described using the ‘renormalized’
magnetic force theorem given by Bruno (2003 Phys.~Rev.~Lett. 90 087205).
This conclusion is confirmed by ab initio calculations for Fe and
Ni.
