Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: iCISCF: An Iterative Configuration Interaction-based
  Multiconfigurational Self-consistent Field Theory for Large Active Spaces   An iterative configuration interaction (iCI)-based multiconfigurational
self-consistent field (SCF) theory, iCISCF, is proposed to handle systems that
require large complete active spaces (CAS). The success of iCISCF stems from
three ingredients: (1) efficient selection of individual configuration state
functions spanning the CAS, meanwhile maintaining full spin symmetry; (2) the
use of Jacobi rotation for the optimization of active orbitals, in conjunction
with a quasi-Newton algorithm for the core/active-virtual and core-active
orbital rotations; (3) a second-order perturbative treatment of the residual
space left over by the selection procedure (i.e., iCISCF(2)). Just like
selected iCI being a very accurate approximation to CASCI, iCISCF(2) is a very
accurate approximation to CASSCF. Several examples that go beyond the
capability of CASSCF are taken as showcases to reveal the performances of
iCISCF and iCISCF(2).

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The categories of this paper are: cond-mat
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The categories of this paper are: q-fin
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The categories of this paper are: eess
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: econ
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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
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The categories of this paper are: adap-org