[lammps-users] Help with Input script-LAMMPS 2001

Hi

I want to study a certain polymer to study its sorption characteristics for certain gases.

As from the LAMMPS manual and tools directory I made a data file (using msi2lmp tool) which list all the forcefield parameters and the co-ordinates of all the atoms in the polymer for pcff forcefield.

For the next step though I am bit confused.

The route I want to follow to do the simulations is as follows:

  1. Minimize the structure.

(Hence I am using the LAMMPS 2001 version as it has minimizer).

  1. followed by NPT dynamics for 50-100 ps.

  2. Minimize the structure from step 2

  3. NVT dynamics for 200 ps with data acqisition at each 20ps.

Please can someone help me how to write the input script for the above mentioned simulations.

Thanks
AAdesh

If you're running LAMMPS 2001 to do the minimize, then you need to
convert the output to LAMMPS 2005 format (a data file). Then you
can do NVT and NPT in LAMMPS 2005 via the fix nvt and fix npt commands.
All this is in the documentation for those commands. Use some of
the example input scripts in LAMMPS 2005 to get you started.

Steve

Hi

Is there any way that I could find the manual for the 2001 version(fortran) of LAMMPS.
I want to use the “minimize” command using 2001 version as it is not yet available in the latest version.

Aadesh

The 2001 manual is on the download site
http://www.cs.sandia.gov/~sjplimp/download.html

If you scroll down to the LAMMPS section, you'll see a link
for the 2001 manual.

Steve