Questions tagged [intermolecular-forces]

Refers to forces that mediate interaction between molecules, including forces of attraction or repulsion which act between molecules and other types of neighboring particles, e.g. atoms or ions.

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Empirically determining thermostat damping factor

tl;dr Is there a way to determine an appropriate thermostat damping factor given a timestep size and a numerical integration method? I am computing a set of simulations in LAMMPS, using ReaxFF, ...
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How does one compute the boiling point of a liquid made of a particular molecule?

This question is in relation to Anomalous boiling point of "iso-" alkanes on Chemistry SE. I want to compute the boiling point of the different isomers of an n-carbon alkane to check what ...
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Rule-of-thumb for Morse potential cutoff in molecular dynamics?

Is there a rule-of-thumb for selecting a cutoff for the Morse potential in molecular dynamics simulation? For instance, is it typically some multiple of the equilibrium distance?
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Simulating breaking bonds in molecular dynamics

How does one introduce the possibility of breaking a bond in a molecule during MD simulation? I only found the cases when we just introduce the harmonic potential $U_{ij} = \frac{1}{2}k(r_i - r_j)^2$ ...
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1answer
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DFT modeling intermolecular interactions

Density Functional Theory based codes evaluate quite successfully intramolecular forces responsible of the atomic bonding. Within this technique one is able to obtain molecular relaxed structures that ...
22
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1answer
183 views

Benchmarking data for Ewald summation algorithms

Are there good benchmarks available for testing homemade Ewald summation code? Optimally it would be very nice if there was several types of systems. NIST has a very nice benchmark for energies of ...
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What is the appropriate way of determining a value for the Hubbard-like potential U for LDA+U / GGA+U calculations?

It is known that neither LDA or GGA correctly account for the strong on-site Coulomb interaction of localized electrons[1]. A cost-effective way of correcting this is by using a Hubbard-like term $U$. ...
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What are the different ways of calculating dispersion constants?

There are many different dispersion corrections out there. The most famous is D3 [1] (and the new D4 [2]), but there's probably other approaches too. The dispersion energy can be written as: $$ E_{\...
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In molecular mechanics, how are van der Waals forces modelled?

In terms of energy, how are van der Waals forces modelled (are there formulas/laws that govern these)?