Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Long-range magnetic interaction and frustration in double perovskite
  Sr$_{2}$NiIrO$_{6}$   Sr$_{2}$NiIrO$_{6}$ would be a ferromagnetic (FM) insulator in terms of the
common superexchange mechanism between the first nearest neighboring (1NN)
magnetic ions Ni$^{2+}$ ($t_{2g}^{6}e_{g}^{2}$) and Ir$^{6+}$ ($t_{2g}^{3}$).
However, the observed antiferromagnetic (AF) order questions this viewpoint. In
this work, we present first-principles calculations and find that while the 1NN
Ni$^{2+}$-Ir$^{6+}$ exchange is indeed FM, the 2NN and 3NN couplings in the fcc
Ir (and Ni) sublattice are AF. Moreover, the 2NN AF Ir-Ir coupling turns out to
be even stronger than the 1NN FM Ni-Ir coupling, thus giving rise to a magnetic
frustration. Sr$_{2}$NiIrO$_{6}$ hence becomes a distorted low-temperature
antiferromagnet. Naturally, a very similar magnetic property in
Sr$_{2}$ZnIrO$_{6}$ can be explained by the frustrated AF coupling in the fcc
Ir$^{6+}$ sublattice. This work highlights the long-range magnetic interaction
of the delocalized $5d$ electrons, and also addresses why the spin-orbit
coupling is ineffective here.

29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
2
The categories of this paper are: math