CGenFF version 2b5 can now be downloaded from the CGenFF download page as well as the CGenFF section on the MacKerell lab's force field page. Here is an incremental list of changes since CGenFF version 2b4 (copy-pasted from the download page):
  • Changed atom typing scheme for phosphates; partial reparameterization of phosphor-oxygen bonds
  • Eliminated asymmetric dihedrals and impropers - many compounds affected
  • Big purge of "slack" parameters. If you are missing parameters that were present in older versions, please report it in this thread
  • Renumbered atom types in the framework of CHARMM force field re-organization - old psf files are henceforward invalid
  • Added carbamate parameters (RESI DMCA and DECA)
  • Added parameters for styrene (RESI STYR)
  • Miscellaneous new model compounds:
    • 2-Pyridone (RESI 2PYO) and uracil (RESI URAC)
    • 4,6-dioxabicyclo[3.3.0]octan-8-ol (RESI RSRF)
    • 1,2,4-Oxadiazole (RESI OXD4)
    • RESI HDZ1B, another phenylhydrazone model compound
    • methyl triphosphate (RESI METP)
  • Updated parameters for 1,2,4-triazole (RESI TRZ4)
  • Updated OG312 L-J parameters
  • Updated CG2R61 NG311 bond; affected compounds: RESI FEOZ, FETZ
  • Fixed inconsistencies in conjugated double bond parameters - many compounds affected
  • Fixed an incorrect pyridine parameter - affects most pyridines
  • Fixed aniline amide torsion lacking multiplicity 1 term
  • Fixed a copy-paste error in a dihedral parameters in RESI DMP2
  • Fixed atom types and charges on fluor-substituted THF derivatives (RESI T2FD, T2FU, TMFD, TMFU, THNP)
  • Fixed charges on "carbocyclic" nucleotide derivatives (RESI CNGU, CSGU, CNTH, CSTH, CNT1, CNT2, CNT3, CNCY, CSCY)
  • Fixed CG2DC? atom types on RESI TMCH (not conjugated)
  • Fixed CG2DC? atom types on RESI PRAC, PRAL, HDZ2 (conjugated)
  • Fixed atom types on RESI PMHA
  • Fixed atom types on RESI 2AMP
  • Fixed charges on RESI THF2
  • Added missing improper in RESI 3CPY
  • Fixed some IC tables
  • Removed RESI 4HQI because it was broken while fixing parameters it shares with more important model compounds
  • Removed RESI TEAZ, TDAZ because of issues with atom typing that were not trivial to correct - inquire if you need these compounds
  • Removed RESI DMSO in preparation of upcoming sulfur reparameterization - inquire if you need it
  • Renamed protonated TMAO to RESI TMAOP (neutral TMAO is coming soon; inquire if intersted)