Table inner cutoff >= outer cutoff

Hello,

I want to add long range forces to my simulation and I am using pppm. the part of my code which is related to the interactions is this :

kspace_style pppm/disp 1.0e-4
pair_style lj/long/coul/long cut long 1.12
pair_coeff * * 1 1

bond_style harmonic
bond_coeff 1 30 1.2

I just want to have system including lj interactions with 1.12 cut off and coul foces without any specific cut off.
I am getting this warning and then the running process stops and I do not know what to do :

Table inner cutoff >= outer cutoff

Thank you in advance for your time

Hello,

I want to add long range forces to my simulation and I am using pppm. the
part of my code which is related to the interactions is this :

kspace_style pppm/disp 1.0e-4
pair_style lj/long/coul/long cut long 1.12
pair_coeff * * 1 1

bond_style harmonic
bond_coeff 1 30 1.2

I just want to have system including lj interactions with 1.12 cut off and
coul foces without any specific cut off.

​why on earth are you using pppm/disp and lj/long/coul/long, when you do
*not* want long-range contributions for LJ.
much simpler to use plain pppm and lj/cut/coul/long instead.

beside, you still *have* to provide a cutoff for real space coulomb, so you
define the real-space to k-space separation. by default it will use the LJ
cutoff, if explicit coulomb cutoff is given. however, using 1.12 is likely
a bad choice and will shift the balance too far towards k-space.

I am getting this warning and then the running process stops and I do not
know what to do :

Table inner cutoff >= outer cutoff

​that is because by default, the pair style uses a special lookup table for
the real space contribution. your coulomb cutoff is too short for it. you
need to choose a different realspace cutoff for coulomb or turn off
tabulation for coulomb via pair_modify.

please study the manual for more details.

axel.