Directional Potential Functions

Functional forms for simple additional potentials

Below are listed the interaction forms available for directional additional potentials acting on individual atoms. All functional forms have an implied origin / reference coordinate defined by some other means (e.g. specified when adding additional potentials to configurations) with $r = r_{i} - r_{origin}$, as well as a directional vector component $v$ which defines the interaction.

Keyword Parameters Description
LJ $\epsilon$
$\sigma$
Cylindrical Lennard-Jones 12-6 potential acting perpendicular to $v$. $$ E = 4 \epsilon \left( \left(\frac{\sigma}{r}\right)^{12} - \left(\frac{\sigma}{r}\right)^6 \right) $$ $$ F = -48 \epsilon \left( \frac{\sigma^{12}}{r^{13}} - \frac{1}{2} \frac{\sigma^6}{r^7} \right) $$ $epsilon$ and $sigma$ are used as-is and are not combined with the target atom’s parameters.
Last modified April 23, 2024: Update release notes. (70ff745)