Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structure, Properties, and Disorder in the New Distorted-Hollandite
  PbIr4Se8   The synthesis and physical properties of the new distorted-Hollandite
PbIr4Se8 are reported. Powder X-ray diffraction and transmission electron
microscopy show that the structure consists of edge- and corner-sharing IrSe6
octahedra, with one-dimensional channels occupied by Pb. The structure contains
Se-Se anion-anion bonding, leading to an electron count of
Pb2+(Ir3+)4(Se2)2-(Se2-)6, confirmed by bond-valence sums and diamagnetic
behavior. Structural and heat capacity measurements demonstrate disorder on the
Pb site, due to the combination of lone-pair effects and the large size of the
one-dimensional channels. Comparisons are made to known Hollandite and
pseudo-Hollandite structures, which demonstrates that the anion-anion bonding
in PbIr4Se8 distorts its structure, to accommodate the Ir3+ state. An
electronic structure calculation indicates semiconductor character with a band
gap of 0.76(11) eV.

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The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
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The categories of this paper are: nlin
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con