Hello

I hope you have a good day

I have a questions

My question is, can I use the **coul/wolf** command for the error function potential ? And how can I calculate the screening factor for sodium?

Thank you very much

Hello

I hope you have a good day

I have a questions

My question is, can I use the **coul/wolf** command for the error function potential ? And how can I calculate the screening factor for sodium?

Thank you very much

You have to be more specific in what particular potential function you want to implement.

Most likely the answer to your question is “no”. For starters, the potential in pair style coul/wolf not only uses the error function, but also has a term using the complementary error function.

If this is a pairwise additive potential function, it can likely be approximated with pair_style table command — LAMMPS documentation

This is not something you calculate, but rather is dependent on your specific system and its parameterization.

Thank you very much for your response. I have one question,how can I use one term of Wolf summation? if I can’t , so how can I import this potential which is in attached file?

I was very thanksful you are considering my problem

No. It would not work anyway, because your potential function is different.

This function is useless in this form without knowing what the individual parameters mean and - ideally - what publication this is taken from. I can guess most of them, but not all.

At any rate, this function looks different than anything implemented in LAMMPS and unless it can be transformed into any of those, you would have to implement a new pair style in C++ to be able to use it.

I try my best, many thanks for your answer

q is an effective charge, R is a bond distance, and ρ is the

screening factor

How is this screening factor determined? It looks like this may be different for each pair of particles or is it depending on the charge? or on the particle type and thus an input parameter?

What kind of particles does this represent? What kind of model is this? Are there publications?

The screening factor ρ(A1-A2)=(rA1+rA2)f is assumed to equal the sum of the covalent radii rAi of the two ions involved times a factor f that depends on the average absolute cation electronegativity and the average cation charge in the compound.

I try to calculate the diffusion coefficient of Na in NaZr2P3O12 7 Li in LiZr2P3O12 (NASICON materials)

Ok, thanks.

That means that if you want to use this kind of potential you need to implement a new pair style in C++.

https://docs.lammps.org/Modify.html

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Thank you I really appreciate your help.