[lammps-users] Using pair_style meam

Dear developers,

I am using pair_style meam with the generic file library.meam with one or two element here Al and Si, present in library.meam file.
In both cases I have an error message : ERROR: Incorrect args for pair coefficients (src/MEAM/pair_meam.cpp:206)

My Lammps version is of Sept2021

I have attached the input script and the corresponding log file.
The file library.meam is copied in the working directory.
I understand that it should run without the 2nd file.

If the second filename is specified as NULL, no parameter file is read, which simply means the generic parameters in the library file are used. Use of the NULL specification for the parameter file is discouraged for systems with more than a single element type (e.g. alloys), since the parameter file is expected to set element interaction terms that are not captured by the information in the library file.

Adding NULL instead of the 2nd file does change the error message.

lmp -h confirmd MEAM Package is installed

Installed packages:

ASPHERE BOCS BODY BROWNIAN CG-DNA CG-SDK CLASS2 COLLOID COLVARS CORESHELL
DIELECTRIC DIFFRACTION DIPOLE DPD-BASIC DPD-MESO DPD-REACT DPD-SMOOTH DRUDE
EFF EXTRA-COMPUTE EXTRA-DUMP EXTRA-FIX EXTRA-MOLECULE EXTRA-PAIR FEP GRANULAR
INTERLAYER KSPACE MANYBODY MC MEAM MISC ML-IAP ML-SNAP MOFFF MOLECULE OPENMP
OPT ORIENT PERI PHONON PLUGIN POEMS QEQ REACTION REAXFF REPLICA RIGID SHOCK
SPH SPIN SRD TALLY UEF YAFF

lubricateU/poly lubricate/omp lubricate/poly lubricate/poly/omp
mdpd mdpd/rhosum meam meam/c meam/spline
meam/spline/omp meam/sw/spline mie/cut mliap

Thanks for help
Best
Pascal

testAlSi.in (546 Bytes)

logAlSi-meam.lammps (926 Bytes)

testAl.in (457 Bytes)

logAl-meam.lammps (768 Bytes)

Dear Dr Braud,

I think the problem is that the second file also needs placeholders for the atoms names after it, even with the filename set as NULL.

In testAlSi.in, the correct pair_coeff line becomes pair_coeff * * library.meam Al Si NULL Al Si and similarly in the case of testAl.in with only NULL Al added at the end. With this commands both inputs terminate without error with my version.

Best regards,

Germain.

Hi Germain
Thanks a lot for the advice.
It works pretty well for me.

Best
Pascal