Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electronic structure and magnetism for FeSi$_{(1-x)}$Ge$_x$ from
  supercell calculations   Recent studies of FeSi$_{(1-x)}$Ge$_x$, which found a transition from an
insulating to a magnetic metallic state near $x$=0.25, have revived the
discussion about the role of strong correlation in these systems. Here are spin
polarized band calculations made for 64-atom supercells of FeSi$_{(1-x)}$Ge$_x$
for different $x$ and different volumes for large $x$. The results show that
the small band gap in FeSi is closed for $x \geq 0.3$, because of both
substitutional disorder and increased volume. Ferromagnetism appears near this
composition and becomes enforced for increasing $x$. The $x$-dependence of the
electronic specific heat can be understood from the exchange splitting of the
density-of-states near the gap. Strong volume dependencies for the properties
of FeGe suggest experiments using pressure instead of $x$ for investigations of
the gap.

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The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
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The categories of this paper are: eess
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex