[lammps-users] WARNING: Table inner cutoff >= outer cutoff - Is this a problem?

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1

I am running the attached abbreviated code (I can give more details if necessary), but seeing the following warning:
Table inner cutoff >= outer cutoff:
(From LAMMPS error messages) You specified an inner cutoff for a Coulombic table that is longer than the global cutoff. Probably not what you wanted.

My box dimensions are (L_x,L_y,L_z) = (1,1,1.5) and I specify the r_cut for Coulombic interactions to be 0.6. I am not sure what I am doing incorrectly and thus do not know how to fix it. If it is still successfully running, is it really a problem? Any help would be appreciated.

Thanks in advance,

Brian

Selections from my code:

Initialize simulation box

dimension 3
boundary p p f
units lj
atom_style charge

Create geometry

region simbox block -0.5 0.5 -0.5 0.5 -0.75 0.75 units box
create_box 2 simbox

#INSERT 500 particles

Create groups

group A type 1
group C type 2
group ions type 1 2

Set masses

mass 1 1.0
mass 2 1.0

Set potentials

pair_style lj/cut/coul/long 0.0125 0.6 #WHY IS THIS WRONG?
pair_coeff * * 0.4 0.005
kspace_style ewald 1E-4
kspace_modify slab 3.0
dielectric 100 #1/0.01

Misc

neighbor 1 nsq
neigh_modify delay 0 every 1 check yes page 1000000 one 10000

fix anode all wall/lj93 zlo -0.75 10 0.366246 0.25 units box
fix cathode all wall/lj93 zhi 0.75 10 0.366246 0.25 units box

2

The LJ cutoff (0.0125) is not what is being referred to. This
is the table cutoff for the Coulomb only portion, set by pair_modify tabinner,
which defaults to sqrt(2.0) which is > 0.6, hence the warning. Most
people run LJ units with sigma = 1.0, hence that is a reasonable default.
You appear to be running with a box size of one, and a tiny sigma, since
your cutoffs are so small. Hence you will need to adjust tabinner.

Steve