Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: van der Waals interaction in nanotube bundles : consequences on
  vibrational modes   We have developed a pair-potential approach for the evaluation of van der
Waals interaction between carbon nanotubes in bundles.
  Starting from a continuum model, we show that the intertube modes range from
$5 cm^{-1}$ to $60 cm^{-1}$. Using a non-orthogonal tight-binding approximation
for describing the covalent intra-tube bonding in addition, we confirme a
slight chiral dependance of the breathing mode frequency and we found that this
breathing mode frequency increase by $\sim$ 10 % if the nanotube lie inside a
bundle as compared to the isolated tube.

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The categories of this paper are: plasm-ph
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The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
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The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
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The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org