OPLS/CM1A Parameter Generator for Organic Ligands

  • LigParGen is a web-based service that provides force field (FF) parameters for organic molecules or ligands, offered by the Jorgensen group.
  • LigParGen provides bond, angle, dihedral, and Lennard-Jones OPLS-AA parameters with 1.14*CM1A or 1.14*CM1A-LBCC partial atomic charges.
  • Server provides parameter and topology files for commonly used molecular dynamics and Monte Carlo packages OpenMM, Gromacs, NAMD, CHARMM, LAMMPS, TINKER, CNS/X-PLOR, Q, DESMOND, BOSS and MCPRO. Also, the PQR file is generated.
  • Supported input formats: SMILES, MOL and PDB.
  • Maximum ligand size allowed is 200 atoms.
  • Check this link to use LigParGen software from command-line in your local computer.
  • Please, report any issue clicking in the following link: LigParGen issues


Molecule Optimization Iterations   

Select charge model:

1.14*CM1A-LBCC    (Neutral molecules)

1.14*CM1A 1    (Neutral or Charged molecules)

Molecule charge

1 For charged molecules, CM1A charges are NOT scaled by a factor 1.14