Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: New angles on standard force fields: towards a general approach for
  treating atomic-level anisotropy   Nearly all standard force fields employ the 'sum-of-spheres' approximation,
which models intermolecular interactions purely in terms of interatomic
distances. Nonetheless, atoms in molecules can have significantly non-spherical
shapes, leading to interatomic interaction energies with strong orientation
dependencies. Neglecting this 'atomic-level anisotropy' can lead to significant
errors in predicting interaction energies. Herein we propose a simple,
transferable, and computationally-efficient model (MASTIFF) whereby
atomic-level orientation dependence can be incorporated into ab initio
intermolecular force fields. MASTIFF includes anisotropic exchange-repulsion,
charge penetration, and dispersion effects, in conjunction with a standard
treatment of anisotropic long-range (multipolar) electrostatics. To validate
our approach, we benchmark MASTIFF against various sum-of-spheres models over a
large library of intermolecular interactions between small organic molecules.
MASTIFF achieves quantitative accuracy with respect to both high-level
electronic structure theory and experiment, thus showing promise as a basis for
'next-generation' force field development.

31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs