Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Robust, accurate, and efficient: quantum embedding using the Huzinaga
  level-shift projection operator for complex systems   Wave function (WF) in density functional theory (DFT) embedding methods
provide a framework for performing localized, high accuracy WF calculations on
a system, while not incurring the full computational cost of the WF calculation
on the full system. In order to effectively partition a system into localized
WF and DFT subsystems, we utilize the Huzinaga level-shift projection operator
within an absolutely localized basis. In this work, we study the ability of the
absolutely localized Huzinaga level-shift projection operator method to study
complex WF and DFT partitions, including partitions between multiple covalent
bonds, a double bond, and transition metal-ligand bonds. We find that our
methodology can accurately describe all of these complex partitions.
Additionally, we study the robustness of this method with respect to the WF
method, specifically where the embedded systems were described using a
multiconfigurational WF method. We found that the method is systematically
improvable with respect to both the number of atoms in the WF region and the
size of the basis set used, with energy errors less than 1 kcal/mol.
Additionally, we calculated the adsorption energy of H$_2$ to a model of an
iron metal organic framework (Fe-MOF-74) to within 1 kcal/mol compared to
CASPT2 calculations performed on the full model while incurring only a small
fraction of the full computational cost. This work demonstrates that the
absolutely localized Huzinaga level-shift projection operator method is
applicable to very complex systems with difficult electronic structures.

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The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
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The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: ao-sci
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org