Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ab initio Derivation of Low-Energy Model for Alkali-Cluster-Loaded
  Sodalites   An effective low-energy model describing magnetic properties of
alkali-cluster-loaded sodalites is derived by {\em ab initio} downfolding. We
start with constructing an extended Hubbard model for maximally localized
Wannier functions. {\em Ab initio} screened Coulomb and exchange interactions
are calculated by constrained random phase approximation. We find that the
system resides in the strong coupling regime and thus the Heisenberg model is
derived as a low-energy model of the extended Hubbard model. We obtain
antiferromagnetic couplings $\sim$ $O$(10 K), being consistent with the
experimental temperature dependence of the spin susceptibility. Importance of
considering the screening effect in the derivation of the extended Hubbard
model is discussed.

22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
9
The categories of this paper are: nlin