Dear Lammps users,
I am getting some problems when trying to use the implementation of the core-shell model of Mitchell and Finchham in order to perform calculations on zinc sulfide.
I use a Coulomb-Buckingham potential combined with the core-shell option and LAMMPS version of august 10th 2015
I created my crystal and performed a minimization but when I initialize the temperature of the system in order to perform a NVE and NPT thermalisation, I lose the bond between core and shell (ERROR on proc: Bond atoms 1 385 missing on proc 0 at step 157 (…/neigh_bond.cpp:65)) .
The only solution I found is to put a very small timestep (2.10^-10 ps).
But this solution will dramatically impact the computational time since my final objective is to determine diffusion coefficient by MSD calculation at different temperatures.
Does someone have a better idea to solve this problem or any explanation about the origin of the non-sense forces causing the bonds to disappear?
You will find enclosed the input files (in.ZnX3, pot.mod and init.mod) and the output file (error_code).
I hope one of you can help me.
Thank you in advance
Best regards.
Kévin Perrin
Ph. D. Student
IFP Energies nouvelles – Direction Catalyse et Séparation
Etablissement de Lyon
Rond-point de l’échangeur de Solaize - BP 3
69360 Solaize - France
Tél. : 04 37 70 31 91
kevin.perrin@…2875…
www.ifpenergiesnouvelles.fr
error_code (8.33 KB)
in.ZnX3 (4.48 KB)
init.mod (970 Bytes)
pot.mod (1.87 KB)
Did you read Section 6.26 of the manual and successfully
run the examples/coreshell script? Are yiou using compute temp/cs
and the temp init strategy in examples/coreshell?
I would try the current version of LAMMPS (may have been
some bug fixes in last year), and if that all fails, send
an email to Hendrik.
Steve
Dear Steve,
Thank you for your advice and prompt answer.
I just found a solution, I did not pay attention on the shell weight and I put a value near to zero. When I increase the shell weight (1-2 % of the atom weight), The calculation runs with a reasonable timestep .
Moreover this change seems not to impact diffusion coefficient calculation according to Mitchell and Fincham (http://dx.doi.org/10.1088/0953-8984/5/8/006).
Best regards,
Kévin Perrin
Doctorant
IFP Energies nouvelles – Direction Catalyse et Séparation
Etablissement de Lyon
Rond-point de l’échangeur de Solaize - BP 3
69360 Solaize - France
Tél. : 04 37 70 31 91
kevin.perrin@…2875…
www.ifpenergiesnouvelles.fr
Envoyé : mercredi 26 octobre 2016 16:27
Dear Steve,
Thank you for your advice and prompt answer.
I just found a solution, I did not pay attention on the shell weight and I
put a value near to zero. When I increase the shell weight (1-2 % of the
atom weight), The calculation runs with a reasonable timestep .
Moreover this change seems not to impact diffusion coefficient calculation
according to Mitchell and Fincham (http://dx.doi.org/10.1088/
0953-8984/5/8/006).
kevin,
is this information properly conveyed in the documentation? if not, please
suggest changes or additions.
thanks,
axel.