dear developers
My LAMMPS version is Windows 29Aug2024
I have an error message for when using meam pair_style that was not occuring with Lammps version 29Sep2021
The code extract is:
mass 1 63.546
mass 2 28.0855
mass 3 4.0026
group CuS type 1
group SiS type 2
group He type 3
pair_style hybrid meam lj/cut 4.0 table linear 4000
pair_coeff * * meam library.meam AlS SiS MgS CuS FeS AlSiMgCuFe.meam CuS SiS NULL # Cu-Cu Si-Si Cu-Si
pair_coeff 1 3 table tableHeCu.txt moliere # Cu-He
pair_coeff 2 3 table tableHeSi.txt moliere # Si-He
pair_coeff 3 3 lj/cut 0.000881 2.56 # He-He
and the error message is:
pair_style hybrid meam lj/cut 4.0 table linear 4000
pair_coeff * * meam library.meam AlS SiS MgS CuS FeS AlSiMgCuFe.meam CuS SiS NULL # Cu-Cu Si-Si Cu-Si
Reading MEAM library file library.meam with DATE: 2012-06-29
ERROR on proc 0: Did not find all elements in MEAM library file, missing: AlS (src/MEAM/pair_meam.cpp:488)
Last command: pair_coeff * * meam library.meam AlS SiS MgS CuS FeS AlSiMgCuFe.meam CuS SiS NULL # Cu-Cu Si-Si Cu-Si
I tried
pair_coeff * * meam library.meam SiS CuS AlSiMgCuFe.meam CuS SiS
pair_coeff * * meam library.meam AlS SiS MgS CuS FeS AlSiMgCuFe.meam CuS SiS
without success. But I think it can not works since there are 3 three type of atoms and the 3rd one is not included in meam. So We should use NULL instead.
May be something has changed in writing the pair_coeff for this meam file parameters ?
Have you an idea of what the problem is ?
Best regards
Pascal
If anything, LAMMPS is now checking more carefully for correct and consistent input.
Sorry, but that logic is wrong. You must not use a MEAM library file that is not consistent with the MEAM user file and that is clearly the case here. The library.meam file bundled with LAMMPS does contain settings for all those requested “elements”, so the question is: where did your file come from?
$ grep -A2 -E '(AlS|SiS|MgS|CuS|FeS)' library.meam
'AlS' 'fcc' 12. 13 26.9815
4.64 2.04 3.00 6.0 1.50 4.05 3.353 1.07
1.0 +4.50 -2.30 8.01 1.0 -5
'SiS' 'dia' 4. 14 28.086
4.87 4.4 5.5 5.5 5.5 5.431 4.63 1.
1.0 2.05 4.47 -1.80 2.2 -5
'MgS' 'hcp' 12. 12 24.305
5.52 4.0 3.0 0.2 1.2 3.194 1.51 0.80
1.0 10.04 9.49 -4.3 0.63 -5
'CuS' 'fcc' 12. 29 63.54
5.11 3.634 2.20 6 2.20 3.62 3.54 1.07
1.0 4.91 2.49 2.95 1.10 -5
'FeS' 'bcc' 8 26 55.847
5.0270 3.500 2 1.00 1 2.851 4.28 0.5550
1 -1.6 12.5 -1.40 1.0 -5
Definitely not. That will break the processing logic of the pair_coeff command for MEAM.
The cleanest solution is to use a proper library.meam file.
But since the missing element is not used in the type to element mapping, a hackish solution would be to substitute it with a different element. Since that element is not used, it will not matter that the parameters would be for a “wrong” element.
A better solution would be to edit the MEAM user file, to only contain entries for the elements you use. That means, you would use:
pair_coeff * * meam library.meam SiS CuS SiCu.meam CuS SiS NULL
Where the SiCu.meam file is edited from AlSiMgCuFe.meam as follows:
- all entries referencing elements 1, 3, or 5 are removed
- in the remaining entries element 2 is replaced with element 1, and element 4 with element 2
Thank you very much Axel.
Yes I use the library.meam file from LAMMPS potential folder where CuS and SiS are present for use with AlSiMgCuFe.meam file.
This is the reason I was surprised by the comment about didn’t find all ements: AlS…
I will follow your advice for editing a SiCu.meam file, in the way you suggest. ANd I will inform you about what happens…
Thanks a lot again.
Pascal
Please check the file for those entries. They are right at the top. They must be there or else you have a corrupted file. Here are the first lines of library.meam:
# DATE: 2012-06-29 UNITS: metal CONTRIBUTOR: Greg Wagner, [email protected] CITATION: Baskes, Phys Rev B, 46, 2727-2742 (1992)
# meam data from vax files fcc,bcc,dia 11/4/92
# elt lat z ielement atwt
# alpha b0 b1 b2 b3 alat esub asub
# t0 t1 t2 t3 rozero ibar
'AlS' 'fcc' 12. 13 26.9815
4.64 2.04 3.00 6.0 1.50 4.05 3.353 1.07
1.0 +4.50 -2.30 8.01 1.0 -5
'SiS' 'dia' 4. 14 28.086
4.87 4.4 5.5 5.5 5.5 5.431 4.63 1.
1.0 2.05 4.47 -1.80 2.2 -5
'MgS' 'hcp' 12. 12 24.305
5.52 4.0 3.0 0.2 1.2 3.194 1.51 0.80
1.0 10.04 9.49 -4.3 0.63 -5
'CuS' 'fcc' 12. 29 63.54
5.11 3.634 2.20 6 2.20 3.62 3.54 1.07
1.0 4.91 2.49 2.95 1.10 -5
'FeS' 'bcc' 8 26 55.847
5.0270 3.500 2 1.00 1 2.851 4.28 0.5550
1 -1.6 12.5 -1.40 1.0 -5
Dear Axel
Indeed, the file is corrupted in the first line of the library.memam file. A “Ti” string starts the line.
It reads
Ti# DATE: 2012-06-29 UNITS: metal CONTRIBUTOR: Greg Wagner, [email protected] CITATION: Baskes, Phys Rev B, 46, 2727-2742 (1992)
instead of
# DATE: 2012-06-29 UNITS: metal CONTRIBUTOR: Greg Wagner, [email protected] CITATION: Baskes, Phys Rev B, 46, 2727-2742 (1992)
I did not see this previously. And removing this Ti string, it works.
Thanks a lot again.
Best
Pascal
What was that Shakespeare quote again: There are more things in heaven and earth…?
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