Morse potential¶

This module implements the Morse potential,

$U_\text{Morse}\left(r_{ij}\right) = \epsilon_{ij} \left( 1 - e^{r_{ij}/\sigma_{ij} - r_{\text{min},ij}} \right)^2 - \epsilon_{ij}$

for the interaction between two particles of species $i$ and $j$ .

class halmd.mdsim.potentials.morse(args)¶

Construct Morse potential.

Parameters:

args (table) – keyword arguments
args.particle – instance, or sequence of two instances, of halmd.mdsim.particle
args.epsilon (table) – matrix with elements $\epsilon_{ij}$ (defaults to 1)
args.sigma (table) – matrix with elements $\sigma_{ij}$ (defaults to 1)
args.cutoff (table) – matrix with elements $r_{\text{c}, ij}$
args.minimum (table) – Minimum/equilibrium distance $r_\text{min}$ in units of $\sigma_{ij}$