[lammps-users] Problem with surface introduction

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1

I am doing Simulation on Water Contact angle Analysis with Surface of varying hydrophobicity . I am trying to introduce a surface in z=0 plane that interacts with water molecules using lj 9-3 potential . But I am getting the error : Cannot use fix wall in periodic dimension . If I change the periodic condition along z to non-periodic then I get the error . Cannot use non-periodic boundaries with PPPM (src/KSPACE/pppm.cpp:215) . How can I manage this considering both k_space style and fix wall into consideration ?
My input file is pasted below:

units real
atom_style full
boundary p p p

read_data data.800spce

pair_style lj/cut/coul/long 10 12
kspace_style pppm 1.0e-4

pair_coeff 1 1 0.15535 3.166
pair_coeff * 2 0.0000 0.0000

bond_style harmonic
angle_style harmonic
dihedral_style none
improper_style none

bond_coeff 1 1000.00 1.000
angle_coeff 1 100.0 109.47

special_bonds lj/coul 0.0 0.0 0.5

neighbor 2.0 bin
neigh_modify every 1 delay 10 check yes

timestep 1.0

thermo_style one
thermo 50

dump 1 all custom 2000 800.comp_*. id xs ys zs type type

fix 1 all wall/lj93 zlo 0.0 3.166 0.155 10 pbc no

fix 2 all nvt temp 300.0 300.0 100.0

fix 3 all gravity 9.8e-20 vector 0 0 1

run 2000000

2

You can trying with this:

kspace_modify slab 3.0
3

Dear Vibhuti,
I think the problem persists in your fix wall command. I would like to suggest to you that in the fix wall command you have chosen a parameter to be 10. Instead of that you increase the parameter by 2 or 3 times of the x or y directional box length. Hope it works.

Thanks.
Jyoti Roy.