Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Multi-Orbital Molecular Compound (TTM-TTP)I_3: Effective Model and
  Fragment Decomposition   The electronic structure of the molecular compound (TTM-TTP)I_3, which
exhibits a peculiar intra-molecular charge ordering, has been studied using
multi-configuration ab initio calculations. First we derive an effective
Hubbard-type model based on the molecular orbitals (MOs) of TTM-TTP; we set up
a two-orbital Hamiltonian for the two MOs near the Fermi energy and determine
its full parameters: the transfer integrals, the Coulomb and exchange
interactions. The tight-binding band structure obtained from these transfer
integrals is consistent with the result of the direct band calculation based on
density functional theory. Then, by decomposing the frontier MOs into two
parts, i.e., fragments, we find that the stacked TTM-TTP molecules can be
described by a two-leg ladder model, while the inter-fragment Coulomb energies
are scaled to the inverse of their distances. This result indicates that the
fragment picture that we proposed earlier [M.-L. Bonnet et al.: J. Chem. Phys.
132 (2010) 214705] successfully describes the low-energy properties of this
compound.

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The categories of this paper are: econ
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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
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The categories of this paper are: atom-ph
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The categories of this paper are: eess
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The categories of this paper are: stat
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The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: physics
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The categories of this paper are: chao-dyn
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The categories of this paper are: bayes-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-ex