SHIFT-POT

NAME

SHIFT-POT - This command provides an alternative for the soft-core regularization when $r_{ij}\rightarrow 0$. The Coulomb (direct lattice only) and LJ potentials are right-shifted by a $\lambda$-dependent positive $s$-term, i.e $1/r_{ij} \rightarrow 1/(r_{ij} + \lambda_{ij}s)$ or $(\sigma_{ij}/r_{ij})^n \rightarrow (\sigma_{ij}/(r_{ij}+\lambda_{ij}s\sigma_{ij}))^n$, so that these potential functions have finite derivatives when $r_{ij}\rightarrow 0$ and $\lambda_{ij}\rightarrow 1$.

SYNOPSIS
SHIFT-POT    $s_{\rm el}$    $s_{\rm LJ}$

DESCRIPTION
$s_{\rm el}$ and $r_{LJ}=s_{\rm LJ}\sigma_{ij}$ (in Å) are the shift distances for the Coulomb and LJ potential.

DEFAULTS
$s_{\rm el}=4.0$   $s_{\rm LJ}=0.35$

WARNINGS
This command is not supported in the vector (KNL) force_alchemy routine.