Dear LAMMPS users,
I would like to ask if there is any possibility to employ this kind of potential that is enclosed to this message?
In the equation U_{SLJ} is shifted Lennard-Jones potential, U_M is the morse potential and f(\theta) are the orientation-dependent factors, and U_T is the total potential energy.
While the first two potentials are straightforward and easy to employ, however, is there any option to include these factors (2nd equation in the attached graphic) or it is necessary to
write your own pair_style code?
Thank you for your help in advance.
Sincerely,
Lukasz Baran
Dear LAMMPS users,
I would like to ask if there is any possibility to employ this kind of potential that is enclosed to this message?
In the equation U_{SLJ} is shifted Lennard-Jones potential, U_M is the morse potential and f(\theta) are the orientation-dependent factors, and U_T is the total potential energy.
While the first two potentials are straightforward and easy to employ, however, is there any option to include these factors (2nd equation in the attached graphic) or it is necessary to
write your own pair_style code?
you need to write your own pair style.
please note, that from your description it is not clear how “orientation” is defined. lennard-jones and morse are potentials for point particles which have no orientation.
for particles with an orientation you need use use special atom styles and pair styles and fixes/computes, e.g. for point dipoles, you have to have atom style hybrid sphere and use /sphere integrators to have the dipole orientations updated and torques computed and applied. similarly there is atom style ellipsoid for aspherical particles. so that includes an additional complication unless the orientation is determined differently and does not need to be updated through time integration and you won’t need to compute a torque in addition to the force for each particle.
axel.