0 Ab - initio calculations of exchange interactions , spin - wave stiffness constants , and Curie temperatures of Fe , Co , and

نویسندگان

  • M. Pajda
  • J. Kudrnovský
  • I. Turek
  • V. Drchal
چکیده

We have calculated Heisenberg exchange parameters for bcc-Fe, fcc-Co, and fcc-Ni using the scalar-relativistic spin-polarized Green function technique within the tight-binding linear muffin-tin orbital method and by employing the magnetic force theorem to calculate total energy changes associated with a local rotation of magnetization directions. We have also determined spin-wave stiffness constants and found the dispersion curves for metals in question employing the Fourier transform of calculated Heisenberg exchange parameters. Curie temperatures were calculated both in the mean-field approximation and within the Green function random phase approximation. The latter results were found to be in a better agreement with available experimental data.

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تاریخ انتشار 2000