Hi everyone,
I am trying to simulate a system with a potential which combines the three body Vessal term and the Buckingham term, the form of the potential is:
\phi(i,j) = \frac{Z_iZ_je^2}{r_{ij}} + A_{ij}exp\bigg(\frac{-r_{ij}}{\rho_{ij}}\bigg) + \frac{k}{8(\theta_{ijk}-\pi)^2}\left\{[(\theta_0-\pi)^2-(\theta_{jik}-\pi)^2]\right\}exp\bigg[-\bigg(\frac{r_{ij}}{\rho_{ij}}+\frac{r_{ik}}{\rho_{ik}}\bigg)\bigg]
But in lammps there seems to be no three body Vessal term in pair_style. What can I do to simulate with such a potential?
Thank you!