I wish to calculate the frequency dependent dielectric constant of polymer system by molecular simulation. Can LAMMPS do this? GROMACS have the features to calculate frequency dependent dielectric constants from the autocorrelation function of the total dipole moment.

I would be very grateful indeed for any help you could give me.

I wish to calculate the frequency dependent dielectric constant of polymer system by molecular simulation. Can LAMMPS do this?

not directly.

GROMACS have the features to calculate frequency dependent dielectric constants from the autocorrelation function of the total dipole moment.

I would be very grateful indeed for any help you could give me.

since gromacs supports the VMD molfile plugins (and thus reading LAMMPS trajectories), you could write out a data file, use the vmd topotools plugin to generate a gromacs topology file (not containing a forcefield, but atom types, changes and more that is needed to generate a tpr file sufficient for analysis) and then use the gromacs tool.

or you can use LAMMPS to compute the dipole and write it out with fix print and then post-process that.