Morse potential¶
Potential form of the Morse potential is,
\[\begin{equation*}
E_{ij}(R_{ij}) = D_{ij} \left\{ [\exp (\alpha_{ij} (R_{0,ij} -R_{ij}))-1]^2 -1\right\}
\end{equation*}\]
The potential requires a parameter file in.params.Morse
that has the
following format.
# isp, jsp, D_ij, alpha_ij, R0_ij
1 1 3.7 2.0 1.68
1 2 3.2 1.9 2.5
2 2 2.5 2.1 2.3
In the above case, there are three interactions between 1-1, 1-2 and 2-2. Each interaction has three parameters:
- D_ij: depth of the potential curve (eV)
- alpha_ij: related to the width of the potential well (Ang.^{-1}).
- R0_ij: position of the potential minimum (Ang.)