Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Four-Component Density Matrix Renormalization Group   We present the first implementation of the relativistic quantum chemical two-
and four-component density matrix renormalization group algorithm that includes
a variational description of scalar-relativistic effects and spin-orbit
coupling. Numerical results based on the four-component Dirac-Coulomb
Hamiltonian are presented for the standard reference molecule for correlated
relativistic benchmarks: thallium hydride.

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The categories of this paper are: nlin
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: stat
32
The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: ao-sci
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The categories of this paper are: supr-con