Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exchange-Correlation Energy from Pairing Matrix Fluctuation and the
  Particle-Particle Random Phase Approximation   We formulate an adiabatic connection for the exchange-correlation energy in
terms of pairing matrix fluctuation. This connection opens new channels for
density functional approximations based on pairing interactions. Even the
simplest approximation to the pairing matrix fluctuation, the particle-particle
Random Phase Approximation (pp-RPA), has some highly desirable properties. It
has no delocalization error with a nearly linear energy behavior for systems
with fractional charges, describes van der Waals interactions similarly and
thermodynamic properties significantly better than particle-hole RPA, and
eliminates static correlation error for single-bond systems. Most
significantly, the pp-RPA is the first known functional that has an explicit
and closed-form dependence on the occupied and unoccupied orbitals and captures
the energy derivative discontinuity in strongly correlated systems. These
findings illlustrate the potential of including pairing interactions within a
density functional framework.

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The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: supr-con
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The categories of this paper are: math
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The categories of this paper are: hep-lat
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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: plasm-ph
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The categories of this paper are: funct-an
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol