stoddardd Ford potential

Hi Dear all

I want to use the Stoddard Ford potential in my simulation.The formula for this potential function is given in the attachment.
Should this command “pair_style lj/sf cutoff” be used for this potential function ?

thanks


[Stoddard ford potential.docx|attachment](upload://yZvFtnDlzmF1SOSPDsnZEN90xZ0.docx) (18.7 KB)

Hi Dear all

I want to use the Stoddard Ford potential in my simulation.The formula
for this potential function is given in the attachment.
Should this command "pair_style lj/sf cutoff" be used for this potential
function ?

​no, please compare to: ​

​axel.​

Isn’t this exactly the same as lj/smooth/linear (lammps.sandia.gov/doc/pair_lj_smooth_linear.html)?

Maybe for ease of maintenance we should get rid of one, and to not break backward comptability, just “alias” the other with a PairStyle macro? I can file a pull request if you want.

Isn't this exactly the same as lj/smooth/linear (
lammps.sandia.gov/doc/pair_lj_smooth_linear.html)?

​yup. a few things are computed in a slightly different order, but i
compared some pair_write output for multiple parameter sets and it produced
identical forces and energies.​ funny how people in MD are bound to
re-invent the same basic wheels at least once every decade...

Maybe for ease of maintenance we should get rid of one, and to not break
backward comptability, just "alias" the other with a PairStyle macro? I can
file a pull request if you want.

​no need to. i'll do it myself. i'll also merge the docs and related.​

thanks for noticing,
      axel.