Dear all,
I would first like to thank you in advance for your help. I am a beginner in the use of LAMMPS and I would like to pose my question regarding the calculation of the pair distribution function (PDF) of a configuration of a mixture of two molecules. I use the PCFF force field for my calculations. My configuration is compised of two files (.car and .mdf files) containing the coordinates and the topography. I then use the tool msi2lmp to create a data file that will be used in the in.* file for the MD calculations. I use the correct kewords for the calculation of the RDF and for giving the beginning, middle and end of the file declarations. Instead of an output file I receive a log file with the error
ERROR: Unknown pair style (…/force.cpp:176)
Can someone please help me in the reason this error is produced? Thank you again.
Kind regards,
Andreas Gavrielides
**Andreas Gavrielides**
Doctorant au CIRIMAT-INP Toulouse
SURF Equipe
**Addresse:** CIRIMAT ENSIACET,
4 Allée Emile Monso BP 44362,
31432 Toulouse Cedex 4
**Tel:** (+33) 05 34 32 34 41
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Dear all,
I would first like to thank you in advance for your help. I am a beginner
in the use of LAMMPS and I would like to pose my question regarding the
calculation of the pair distribution function (PDF) of a configuration of a
mixture of two molecules. I use the PCFF force field for my calculations.
My configuration is compised of two files (.car and .mdf files) containing
the coordinates and the topography. I then use the tool msi2lmp to create a
data file that will be used in the in.* file for the MD calculations. I use
the correct kewords for the calculation of the RDF and for giving the
beginning, middle and end of the file declarations. Instead of an output
file I receive a log file with the error
ERROR: Unknown pair style (../force.cpp:176)
Can someone please help me in the reason this error is produced? Thank you
again.
this has absolutely *nothing* to do with computing the radial distribution
function.
the error message tells you instead, that your input file uses a pair style
that is not available in the executable you are using. which in turn means,
that you either have a typo in your input script or executable was compiled
without necessary packages.
in general, what you are doing is a problematic strategy: you are trying to
do too many (new) things at the same time. a better approach is:
- take an existing example input, e.g. the melt example, and see if you can
run that.
- then add the necessary commands to enable g(r) calculation and check
whether the output matches with what you should expect that kind of system
- then try a simple system (e.g. a few simple molecules only) and go
through the process of setting this up through the msi2lmp route until you
get a meaningful simulation
- then try setting up your system of interest and see if you can run a
stable and meaningful MD (check via visualization).
- finally, combine the steps and do simulation and g(r) calculation at the
same time
axel.