[lammps-users] Two tabulated potentials leading to error on coulomb cutoffs

Hello All,

I’m trying to use pair_style table for two potentials at the same time, one is sort of like Lennard Jones, and the other is the short-ranged part of a modified coulomb which is supposed to work with the long-range solver. The two tabulated potentials have different cutoffs and I invoked them with,

pair_style hybrid/overlay table linear 1981 table linear 1000 pppm

and set the coefficients. But an error ‘Coulomb cutoffs of pair hybrid sub-styles do not match’ appears.

The first tabulated potential isn’t intended to work with the long-range solver and I don’t put any keyword like ‘pppm’ with it. Only the second one is coulombic, that’s why I put ‘pppm’ for the second one.

Can Lammps correctly perform this computation in some way without reporting the error?

Thanks in advance!

Best regards,

Why use hybrid/overlay? Why not just combine the two custom potentials into a single table?

Some pairs of atoms only interact through one of the potentials, so l have to tabulate them separately.

please let us know which LAMMPS version you are using. you should always mention that when reporting issues.

I’m using the version of 16 Mar 2018. Thanks.

I’m using the version of 16 Mar 2018. Thanks.

that is part of the problem. If you upgrade to the latest version the cutoff check will be more specific. That issue was addressed last summer.