Dear lammps users,

I have a really possibly really trivial question about lennard jones in lammps.

Lammps uses a version of LJ in the form:

E=4 e [ ( )^12 - ( )^6]

while searching for parameters to be used i found many times them to be used in the form:

E= e [ ( )^12 - 2*( )^6]

There any way to change the form in lammps or should i try to adapt the parameters to reproduce the same curve?

Kind regards,

Lorenzo

Dear lammps users,

I have a really possibly really trivial question about lennard jones in lammps.

Lammps uses a version of LJ in the form:

E=4 e [ ( )^12 - ( )^6]

while searching for parameters to be used i found many times them to be used in the form:

E= e [ ( )^12 - 2*( )^6]

There any way to change the form in lammps or should i try to adapt the parameters to reproduce the same curve?

this question has been asked many times (you should have done some

more research on it) and the answer is, that they are the *same*

potential, just a different definition of sigma. The first has sigma

to be the value where the potential is zero, the second has sigma to

be the minimum of the potential, they are different by a factor

2**(1/6). just insert sigma = sigma' * 2**(1/6) into the second

expression to see.

axel.