Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Metal-Organic Superlattices Induced by Long-Range Repulsive Interactions
  on a Metal Surface   Chains of Na atoms and dicyanovinyl-quinquethiophene (DCV5T-Me2) molecules
with ionic bonds form a superlattice on Au(111). Through a detailed analysis of
the interchain distances obtained from scanning tunneling microscopy images at
various molecular coverages, we found that the chain arrangement substantially
deviates from a random distribution of noninteracting chains. Instead, the
distribution of chain spacings provides evidence for the existence of an
interchain long-range repulsive potential. Furthermore, the experimental
results can be modeled by a repulsive potential with a 1/d distance dependence,
characteristic of Coulomb interactions. Density functional theory calculations
of free-standing molecular chains reveal a charge depletion at the periphery of
the chains, which is attributed to the intrinsic polar property of the molecule
and is responsible for the long-range repulsion.

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The categories of this paper are: atom-ph
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The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
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The categories of this paper are: funct-an
16
The categories of this paper are: stat
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The categories of this paper are: supr-con
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs