[lammps-users] problems about minimize

Hi all,

I am computing the graphene nano-ribbon with triangle shape.

I found that it can’t run even minimize.

In the former computation, I only computed the traditional grahene-nano-ribbon with the same width. It works well. The following is my input script and dat.file

tri_graphene nano-ribbon

units metal

dimension 3

boundary s s p

atom_style atomic

#create geometry

read_data read.dat

neighbor 3.0 bin

neigh_modify delay 0

pair_style airebo 3.0 0 0

pair_coeff * * CH.airebo C C C

#restrained in 2d force

fix 2d all enforce2d

#minimize the system

thermo 10

dump 1 all xyz 10 gnr.xyz

minimize 1.0e-8 1.0e-8 100000 100000


  • –Nwei

I found that it can't run even minimize.

What does this mean?


I am computing the properties of graphene which is a 2D material. It, lammps, works

well to deal with the regular shapes, like square, rectangle. But there are some problems

when I handle the triangle and pie shapes, which have unequal width.

The results of lammps of the 2D-triangle-model are as following:

Step Temp E_pair E_mol TotEng Press Volume

0 0 inf 0 inf nan 3653.6999

1 0 inf 0 inf nan 3653.6999

I don’t know am I describe my question clearly.

2009/10/23 Steve Plimpton <[email protected]>

If you're getting infinite energy on timestep 0 (for either dynamics or
minimization) then there is something wrong with your input geometry
or potential parameters.


See if coordinates of two atoms are same.