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Noncollinear Magnetic Structures in Small Compact Clusters

  • M. A. Ojeda-López
  • J. Dorantes-Dávila
  • G. M. Pastor

Abstract

We investigate the properties of complex magnetic structures in small compact clusters including noncollinear arrangements of local magnetic moments, spin density waves and charge density waves. The Hubbard Hamiltonian is solved within the unrestricted Hartree-Fock (UHF) approximation without imposing any symmetry constraints nei­ther to the size or orientation of the local magnetic moments nor to local charge densities. For icosahedral and fcc-like clusters having N = 13 atoms, and for band-fillings close to half-band, the most stable solutions of UHF equations are discussed as a function of the Coulomb interaction strength U/t. The role of noncollinear ar­rangements of spins in the ground-state magnetic behavior is analyzed. The high connectivity of these compact clusters and the tendency to antiferromagnetic order between nearest-neighbors spins close to half-band filling results in magnetic frustra­tions and in remarkable noncollinear-spin solutions.

Keywords

Hubbard Model Nearest Neighbor Magnetic Order Charge Density Wave Local Magnetic Moment 
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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • M. A. Ojeda-López
    • 1
  • J. Dorantes-Dávila
    • 1
  • G. M. Pastor
    • 2
  1. 1.Instituto de FísicaUniversidad Autónoma de San Luis PotosíSan Luis Potosí, S. L. P.Mexico
  2. 2.Laboratoire de Physique QuantiqueUniversité Paul SabatierToulouseCedexFrance

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