Hi everyone,

I am studying interactions between water and CNT and comparing different force fields. For some calculations, I need to get the pairwise forces and energies. I think that using compute pair/local will be useful. However, one of the force fields requires the use of the hybrid pair style, combining REBO and tip4p potentials. I am no interested in the interactions of pairs of C within the CNT; I want the force and energy between the pairs of C - water, that are modeled with LJ potential. How can I get these values? Do I need a rerun for this? If so, changing the CNT potential to a pairwise and using pair/local would do the trick since there is no time integration in the rerun? Is there a different approach to get these values, like postprocessing?

I am using LAMMPS version 29Jun18

Thank you very much for your help.

Jose.

Hi everyone,

I am studying interactions between water and CNT and comparing different force fields. For some calculations, I need to get the pairwise forces and energies. I think that using compute pair/local will be useful. However, one of the force fields requires the use of the hybrid pair style, combining REBO and tip4p potentials. I am no interested in the interactions of pairs of C within the CNT; I want the force and energy between the pairs of C - water, that are modeled with LJ potential. How can I get these values? Do I need a rerun for this? If so, changing the CNT potential to a pairwise and using pair/local would do the trick since there is no time integration in the rerun? Is there a different approach to get these values, like postprocessing?

i think recording a trajectory and then using rerun with only the one pair style of interest set and the interaction energies for all other components set to zero is the way to go about this.

axel.