MEAM potential for Mo Si

Hello,

i’m trying to use the MEAM Potential for Mo-Si from this Paper[Baskes:"Atomistic potetntials for the molybdenum-silicon system], but i’m not able to reproduce the lattice constants and energies for Mo3Si. This is my library-file:

#MEAM-Parameters for Mo and Si

elt lat z ielement atwt

alpha b0 b1 b2 b3 alat esub asub

t0 t1 t2 t3 rozero ibar

‘Mo’ ‘bcc’ 8 42 95.94
5.85 4.48 5.0 1.0 1.0 3.15 6.810 0.99
1 5.00 9.34 -2.90 1.60 0

‘Si’ ‘dia’ 4 14 28.0855
4.87 4.40 5.5 5.5 5.5 5.43 4.630 1.00
1 2.05 4.47 -1.8 2.05 0

And this is the parameter-file i created:

Cmin(2,2,2) = 2.0
Cmax(2,2,2) = 2.6
Cmin(1,1,1) = 0.8

nn2(1,1)=1
nn2(1,2)=1
nn2(2,2)=1

lattce(1,2)=‘b1’
Ec(1,2)=5.92
alpha(1,2)=5.80
re(1,2)=2.70
Cmax(2,1,2) = 2.6
Cmin(1,2,2) = 0.8

rc = 4.3
ialloy=1
augt1=0
emb_lin_neg=1
bkgd_dyn=1

It would be really nice if you could help me. I think there is something wrong in the parameter-file.

best wishes Robert

Hello Robert,

I would try ibar=-5.

You may need Cmin(1,1,2) = 0.8 (last index is the element in the
center, http://lammps.sandia.gov/doc/pair_meam.html).

I usually specify delta(1,2) instead of Ec(1,2).

You can try to follow
  http://www.ctcms.nist.gov/potentials/Download/AlSiMgCuFe-Jel12/Jelinek_2012_meam.alsimgcufe

-Bohumir