pair_style table WARNING

Dear lammps users,

I get my table potential files via pair_write command and when I use these table files in my simulation, there is a WARNING: 59 of 3000 force values in table are inconsistent with –dE/dr. I searched the manual but didn’t find explanation for this WARNING.

Could you please tell me how to let all force values consistent with –dE/dr? And why do I get this WARNING?

Thank you so much.

Best wishes.

Lily

Dear lammps users,

I get my table potential files via pair_write command and when I use these
table files in my simulation, there is a WARNING: 59 of 3000 force values
in table are inconsistent with –dE/dr. I searched the manual but didn’t
find explanation for this WARNING.

Could you please tell me how to let all force values consistent with –dE/dr?
And why do I get this WARNING?

​this test was added to LAMMPS in order to identify tables where energy and
forces don't match.
you should almost always get this warning, usually just warning you about 1
point, since most potentials have at least one turning point.
it is not a very good test, since it frequently prints false positives, due
to truncation and rounding in the table files.
when you generate your potential tables via pair_write you should not
worry, if your corresponding analytical potential input is working fine.
​sometimes, you can tweak this by changing the number of tabulation points.

axel.​

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