[ESPResSo] analyze pressure and energy problems

[İbrahim İnanç]

Hello,
I have two questions about the program..I would be very happy if you could help me.
First question is I can not calculate pressure in nvt system. Somehow the program is exited with below error message;

One of the processes started by mpirun has exited with a nonzero exit
code.  This typically indicates that the process finished in error.
If your process did not finish in error, be sure to include a "return
0" or "exit(0)" in your C code before exiting the application.

PID 24522 failed on node n0 (127.0.0.1) due to signal 7.

I also tried tutorial.tcl and the code could not iclude pressure coming from the coulomb interaction with the same parameters in the sample scripts..

Second question is I can not put integration time step as 1 for my code. The details of my system and code is as below:
I want to simulate polybutadiene with 32 chains of 128 carbon atoms (32 rep. unit x 4). I changed the units in order to have the real atomic units. But somehow when I put analyze energy command it gives the below error message specially for higher integration steps or higher temperatures..

domain error: argument not in valid range
    while executing
"expr [analyze energy kinetic]"
    ("while" body line 8)
    invoked from within
"while { $i<$n_cycle} {

 integrate $n_steps

When I reduce the temperature to 0.1 then it does the analyze and give numerical results for delt=1.
When I remove the analyze command there is no problem, espresso does the integrations..
Notes: I normalized the input potential coefficient with kbT and mass accordingly so that when I put 1 as integration time step it corresponds to 1 fs.
The code info of my Espresso version  is below;

ESPResSo: 2.0.5e, Last Change: December 20th, 2007
{ Compilation status { MPI lam } { FFTW3 } { PARTIAL_PERIODIC } { ELECTROSTATICS } { ROTATION } { MASS } { EXTERNAL_FORCES } { CONSTRAINTS } { EXCLUSIONS } { COMFORCE } { COMFIXED } { TABULATED } { LENNARD_JONES } { LENNARD_JONES_GENERIC } { MORSE } { BUCKINGHAM } { SOFT_SPHERE } { LJCOS } { BOND_ANGLE_COSINE } { NPT } }
{ Debug status { MPI_CORE FORCE_CORE } }

Thanks...

ibrahim inanc


Phd. Student
Materials Science and Engineering
Sabanci University
MDBF, Orhanli Tuzla 34956
İstanbul, Turkey