Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Complexation of oppositely charged polyelectrolytes: effect of ion pair
  formation   Complexation in symmetric solutions of oppositely charged polyelectrolytes is
studied theoretically. We include polyion crosslinking due to formation of
thermoreversible ionic pairs. The electrostatic free energy is calculated
within the Random Phase Approximation taking into account the structure of
thermoreversible polyion clusters. The degree of ion association is obtained
self-consistently from a modified law of mass action, which includes long-range
electrostatic contributions. We analyze the relative importance of the three
complexation driving forces: long-range electrostatics, ion association and van
der Waals attraction. The conditions on the parameters of the system that
ensure stability of the complex with addition of salt are determined.

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The categories of this paper are: hep-ex
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The categories of this paper are: gr-qc
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: hep-th