Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analytical expressions for the charge-charge local-field factor and the
  exchange-correlation kernel of a two-dimensional electron gas   We present an analytical expression for the static many-body local field
factor $G_{+}(q)$ of a homogeneous two-dimensional electron gas, which
reproduces Diffusion Monte Carlo data and embodies the exact asymptotic
behaviors at both small and large wave number $q$. This allows us to also
provide a closed-form expression for the exchange and correlation kernel
$K_{xc}(r)$, which represents a key input for density functional studies of
inhomogeneous systems.

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The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
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The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol