Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: DFT-based Conformational Analysis of a Phospholipid Molecule (DMPC)   The conformational space of the dimyristoyl phosphatidylcholine (DMPC)
molecule has been studied using Density Functional Theory (DFT), augmented with
a damped empirical dispersion energy term (DFT-D). Fourteen ground-state
isomers have been found with total energies within less than 1 kcal/mol.
Despite differences in combinations of their torsion angles, all these
conformers share a common geometric profile, which includes a balance of
attractive, repulsive and constraint forces between and within specific groups
of atoms. The definition of this profile fits with most of the structural
characteristics deduced from measured NMR properties of DMPC solutions. The
calculated vibrational spectrum of the molecule is in good agreement with
experimental data obtained for DMPC bilayers. These results support the idea
that DMPC molecules preserve their individual molecular structures in the
various assemblies.

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The categories of this paper are: alg-geom
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
2
The categories of this paper are: math
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The categories of this paper are: stat
18
The categories of this paper are: econ