cff93 forcefield in lammps

dear lammps users
i want to implement cff93 in lammps to simulate ethylene carbonate .
is there anyone who has done this to help me ?

Why not just use the class2 styles from the class2 package? The COMPASS article (Sun, J Phys Chem B 102, 7338-7364 (1998), doi: 10.1021/jp980939v) referenced in the class2 LAMMPS documentation states that COMPASS is comparable to CFF93 (and COMPASS is already supported in LAMMPS!). Also, just because the LAMMPS class2 styles are based on COMPASS doesn’t mean that you’re stuck with using COMPASS parameters. You can use whatever class2 parameters you want as long as it matches the format. For the past few years, I’ve been using the PCFF-IFF class2 parameters made by Dr. Heinz’s group at CU Boulder (

Best Regards,