Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gradient corrections to the exchange-correlation free energy   We develop the first order gradient correction to the exchange-correlation
free energy of the homogeneous electron gas for use in finite temperature
density functional calculations. Based on this we propose and implement a
simple temperature dependent extension for functionals beyond the local density
approximation. These finite temperature functionals show improvement over zero
temperature functionals as compared to path integral Monte Carlo calculations
for deuterium and perform without computational cost increase compared to zero
temperature functionals and so should be used for finite temperature
calculations.

7
The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
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The categories of this paper are: astro-ph
2
The categories of this paper are: math
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin