Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-collinear Korringa-Kohn-Rostoker Green function method: Application
  to 3d nanostructures on Ni(001)   Magnetic nanostructures on non-magnetic or magnetic substrates have attracted
strong attention due to the development of new experimental methods with atomic
resolution. Motivated by this progress we have extended the full-potential
Korringa-Kohn-Rostoker (KKR) Green function method to treat non-collinear
magnetic nanostructures on surfaces. We focus on magnetic 3d impurity
nanoclusters, sitting as adatoms on or in the first surface layer on Ni(001),
and investigate the size and orientation of the local moments and moreover the
stabilization of non-collinear magnetic solutions. While clusters of Fe, Co, Ni
atoms are magnetically collinear, non-collinear magnetic coupling is expected
for Cr and Mn clusters on surfaces of elemental ferromagnets. The origin of
frustration is the competition of the antiferromagnetic exchange coupling among
the Cr or Mn atoms with the antiferromagnetic (for Cr) or ferromagnetic (for
Mn) exchange coupling between the impurities and the substrate. We find that Cr
and Mn first-neighbouring dimers and a Mn trimer on Ni(001) show non-collinear
behavior nearly degenerate with the most stable collinear configuration.
Increasing the distance between the dimer atoms leads to a collinear behavior,
similar to the one of the single impurities. Finally, we compare some of the
non-collinear {\it ab-initio} results to those obtained within a classical
Heisenberg model, where the exchange constants are fitted to total energies of
the collinear states; the agreement is surprisingly good.

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The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
34
The categories of this paper are: chem-ph
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The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
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The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int