Dear lammps users,

I am simulating radiation damage in zircon and according to the literature the potential is ZBL for ranges < 1 A , born mayer huggings <10 A and colombic long range.

I tabulated the short ranges potential an joined the two potentials using a fermi function. When i attempted to use a pair_style hybrid/overlay to overlay the colombic long range potential with the tabulated potential, i got an error of “Lost atoms”.

N.b: When creating the tabulated potential, i made all the cutoff distances= 10 A(for zbl and BMH potential)

As a troubleshoot to my problem i tried to simulate the system with just pair_style coul/long, i got NAN results, and when i used pair_style coul/cut i got lost atoms.

i am wondering what could be the reason of these problems?

Please find a part of my input and if you can help me that would be really appreciated.

**Part of the input file***

units metal

atom_style charge

boundary p p p

lattice custom 1 a1 6.607 0 0 a2 0 6.607 0 a3 0 0 5.982 basis 0.0 0.75 0.125 basis 0.0 0.25 0.875 basis 0.5 0.75 0.375 basis 0.5 0.25 0.625 basis 0.0 0.75 0.625 basis 0.0 0.25 0.375 basis 0.5 0.75 0.875 basis 0.5 0.25 0.125 basis 0.0 0.0658 0.1955 basis 0.0 0.9342 0.8045 basis 0.5 0.0658 0.3045 basis 0.5 0.9342 0.6955 basis 0.0 0.5658 0.8045 basis 0.0 0.4342 0.1955 basis 0.5 0.5658 0.6955 basis 0.5 0.4342 0.3045 basis 0.6842 0.25 0.9455 basis 0.8158 0.75 0.4455 basis 0.8158 0.25 0.5545 basis 0.6842 0.75 0.0545 basis 0.1842 0.25 0.5545 basis 0.3158 0.75 0.0545 basis 0.3158 0.25 0.9455 basis 0.1842 0.75 0.4455

region R1 block -1 1 -1 1 -1 1

create_box 3 R1

create_atoms 3 box basis 1 1 basis 2 1 basis 3 1 basis 4 1 basis 5 2 basis 6 2 basis 7 2 basis 8 2 basis 9 3 basis 10 3 basis 11 3 basis 12 3 basis 13 3 basis 14 3 basis 15 3 basis 16 3 basis 17 3 basis 18 3 basis 19 3 basis 20 3 basis 21 3 basis 22 3 basis 23 3 basis 24 3

kspace_style ewald 0.00001

pair_style hybrid/overlay table linear 9999 ewald coul/long 10

pair_coeff 1 1 table zircon21.table ZR-ZR

pair_coeff 1 3 table zircon21.table ZR-O

pair_coeff 2 3 table zircon21.table SI-O

pair_coeff 3 3 table zircon21.table O-O

pair_coeff 1 2 table zircon21.table ZR-SI

pair_coeff 2 2 table zircon21.table SI-SI

pair_coeff * * coul/long

pair_write 1 3 10000 rsq 0.1 10 energy-forceZRO.txt zr-o 3.8 -1.45

pair_write 2 3 10000 rsq 0.1 10 energy-force.txtSIO si-o 2.0 -1.45

pair_write 3 3 10000 rsq 0.1 10 energy-forceOO.txt o-o -1.45 -1.45

**Part of the tabulated potential****

SI-O

N 9999 RSQ 0.001 10

1 0.002 20180.1269905582 13589.3273976564

2 0.003 13386.0395578569 5095.2810331941

3 0.004 9989.56492417 2716.9549052967

4 0.005 7952.1297472636 1697.6776377744

Thanks in advance

Regards,

Meral