Splining pair_style MEAM with ZBL Potential using hybrid/overlay

Greetings to all!

I have been trying to use pair_style hybrid/overlay in the order to spline meam and ZBL potential (RADIATION DAMAGE SIMULATION) . However I am getting error in log file about incorrect pair coefficient format. I know i am doing it wrong somewhere. As per the documentation the ZBL parameter used in the MEAM potential can be turned on and off. The potential file I am using for Cu system specifies it as zero. Is it possible to introduce the ZBL potential using hybrid/overlay? I am attaching error part of the code:

#----------------------DEFINE INTERRACTION POTENTIAL FOR COPPER ATOMS---------------

pair_style hybrid/overlay meam zbl 2.0 3.25
pair_coeff * * library.meam Cu Cu.meam Cu
pair_coeff * * zbl 29 29
neigh_modify every 1 delay 0 check yes

library.Cu.meam (382 Bytes)

Cu.meam (201 Bytes)

Attaching library and parameter files

Obviously yes, because your pair_coeff zbl command is incorrect. It would be correct, if you had two atom types, but you have only one.

No. Pair style hybrid/overlay adds potentials, so there is no splining happening.

The correct way would be to edit the Cu.meam file to enable the ZBL functionality that is already included in the MEAM pair style implementation.

Thankyou Sir. Previously I have used hybrid/overlay to superimpose eam/fs and zbl potential for pure tungsten. Sorry but I couldn’t understand about two atom types.

By the above quote, you mean i can change the zbl parameter in Cu.meam file as 1 to turn it on?

That is not correct either. The correct way for EAM potentials is to create a custom EAM potential file. The pairwise potential function phi is tabulated in these files, so when creating the tabulation, it is possible to modify this potential to “spline in” the ZBL function for short distance and then smoothly transition to the EAM pairwise potential for larger distances.

Thank you for your advice.