My LAMMPS input script fails to read input data file containing ellipsoid information

Dear Sir/Madam,

First, my LAMMPS version is “LAMMPS (7 Aug 2019)”.

Second, I am trying to create a LAMMPS input script called “in.ellipse” that reads the coordinates and other information on ellipsoids from a data file called “initial_coord.dat” using the command (read_data) in the input script “in.ellipse”.

The data file to be read is attached to this email. The input script “in.ellipse” is written below.

However when I run the input script, “in.ellipse”, in the terminal in Linux mint, I obtained the following error message :

“ERROR: Inconsistent ‘ellipsoids’ header value and number of atoms with enabled ellipsoid flags (
Last command: read_data initial_coord.dat add append group big”

The input script “in.ellipse” is the following one:
units lj
atom_style ellipsoid
dimension 2
boundary s s p

lattice sq 0.15
region box block 0 9000 0 9000 0 500
create_box 1 box
read_data initial_coord.dat add append group big

group big type 1

pair_style gayberne 1.0 2.0 1.0 8.0
pair_coeff * * 1.0 1.7 1.7 3.4 3.4 1.0 1.0 1.0

delete_atoms overlap 4 all all

compute 1 all property/atom shapex shapey shapez
compute 2 all property/atom quatw quati quatj quatk

reset_timestep 0
timestep 0.002 # this tells us how long the timestep is

thermo 100
thermo_style custom step temp pe press vol density

dump 1 all custom 10000 lammpstrj.txt.* id type x y &
c_1[1] c_1[2] &
c_2[1] c_2[2] c_2[3] c_2[4]
dump m0 all movie 1000 lammpstrj.mpg type type

fix 1 all nvt/asphere temp 0.3 0.3 0.1
run 10000
unfix 1
undump 1

write_data resultant_conf.dat



I am sure that the problem is in the attached data file called “initial_coord.dat”. Could you please tell what the problem is ?

Much thanks in advance.

Best regards
Mohammed Alhissi

initial_coord.dat (663 KB)

your data file appears to be written by LAMMPS with write_data. however, write_data does not write correct data files for ellipsoids.
this is a known but not yet corrected bug in LAMMPS. please see this issue: