Conditions on the occurrence of magnetic moments in quasicrystals and related phases

[摘要] We analyze the criterion for the appearance of magnetic moments in quasicrystals approximants and liquids Al-Mn. In a Hartree-Fock scheme, it is shown that the Stoner criterion (Un(d)(E-F)greater than or equal to1) does not apply to these systems due to the presence of the pseudogap in the density of states. We give a generalized criterion that can take into account the particular density of state. The main result is that the appearance of a magnetic moment on a Mn atom depends strongly on its position in the crystalline structure. Indeed, some particular positions of the Mn atoms lead to magnetic moments whereas other positions are more stable when the Mn is non-magnetic. This criterion is used to analyze the electronic structure of two approximants (1/1-Al-Pd-Mn-Si and T-AI-Pd-Mn) calculated by the self-consistent linear muffin tin orbitals (LMTO)-ASA method. (C) 2000 Elsevier Science B.V. All rights reserved.

[发布日期] 2000-12-15

[效力级别]  Proceedings Paper

[关键词] magnetism;localized moment;quasicrystal;approximant