Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe2As2,
  LiFeAs, FeSe and FeTe: Electron Correlation and Covalency   Effective low-energy Hamiltonians for several different families of
iron-based superconductors are compared after deriving them from the
downfolding scheme based on first-principles calculations. Systematic
dependences of the derived model parameters on the families are elucidated,
many of which are understood from the systematic variation of the covalency
between Fe-3d and pnictogen-/chalcogen-p orbitals.

29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
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The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con