Zero charge system

Hi,
I would like to ask about using kspace_style.
My system is zero-charge.
I set the command for the simulation
pair_style lj/cut/coul/cut 9.0 9.0
kspace_style ewald 0.0001
But it is said that the command (kspace_style) is not used for zero charge. But I am not sure whether I can run simulation without kspace_style. At this time the results without kspace_style are right?
Thank you.
Sincerely,
Anh

Hi,
I would like to ask about using kspace_style.
My system is zero-charge.
I set the command for the simulation
pair_style lj/cut/coul/cut 9.0 9.0
kspace_style ewald 0.0001
But it is said that the command (kspace_style) is not used for zero charge.

if none of your atoms has any charge, you need neither lj/cut/coul/cut
nor any kspace style. you can use pair_style lj/cut instead.

you *can* use lj/cut/coul/cut, but in any case it is incompatible
with any kspace style except "none".

But I am not sure whether I can run simulation without kspace_style. At this

yes, you can.

time the results without kspace_style are right?

nobody can tell but you. you picked the model, so you have
to implement it correctly. lammps only provides the tools.
you can use it well or use it to shoot yourself in the foot.
lammps doesn't care and will just do what you ask it to do,
for as long as it has been programmed to do it.

axel.