Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exchange effects in elastic collisions of spin-polarized electrons with
  open-shell molecules with $^3\Sigma_g^-$ symmetry   The spin-exchange effect in spin-polarized electron collisions with
unpolarized open-shell molecules, O$_2$, B$_2$, S$_2$ and Si$_2$, has been
studied by the R-matrix method with the fixed-bond approximation. All of these
molecules have ${}^3 \Sigma_{g}^{-}$ symmetry in their ground states. Usual
integrated cross sections with unpolarized electrons has also been studied. We
used the complete active space self consistent field orbitals and put more than
10 target electronic states in the R-matrix models. In electron O$_2$ elastic
collisions, calculated polarization fractions agree well with the experimental
results, especially around the ${}^4 \Sigma_u^-$ resonance. In e-B$_2$, S$_2$
and Si$_2$ elastic collisions, larger spin-exchange effect is observed compared
to the e-O$_2$ elastic collisions. In all four cases, spin-exchange effect
becomes prominent near resonances. This association of resonance and magnitude
of the spin-exchange effect was studied by explicitly removing the resonance
configurations from the R-matrix calculations. In general, spin-exchange effect
is larger in e-B$_2$ collisions than in e-S$_2$ and Si$_2$ collisions, and is
smallest in e-O$_2$ collisions.

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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: stat
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math