62 research outputs found
New Angles on Standard Force Fields: Toward a General Approach for Treating Atomic-Level Anisotropy
Nearly all standard force fields
employ the âsum-of-spheresâ
approximation, which models intermolecular interactions purely in
terms of interatomic distances. Nonetheless, atoms in molecules can
have significantly nonspherical shapes, leading to interatomic interaction
energies with strong orientation dependencies. Neglecting this âatomic-level
anisotropyâ 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
ânext-generationâ force field development
Thermodynamic Analysis of an Integrated Gasification Solid Oxide Fuel Cell Plant with a Kalina Cycle
An Assessment of Transport Property Estimation Methods for AmmoniaâWater Mixtures and Their Influence on Heat Exchanger Size
Thatâs So Cool. Using a Flame to Freeze Water. The Vapor-Absorption Refrigerator and How It Works
Options for low-global-warming-potential and natural refrigerants part I: Constrains of the shape of the PâT and TâS saturation phase boundaries
A new analytical modeling for the determination of thermodynamic quantities of refrigerants
Compressed Liquid Densities, Saturated Liquid Densities, and Vapor Pressures of Hexafluoro-1,3-butadiene (C 4
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