[gmx-users] Ryckeat-Bellemans Potential in Charmm forcefield

[XUEMING TANG]

Hi there

I plan to use Charmm forcefield to simulate a long alkyl chain (C12). When
assigning dihedral parameters to the alkyl chain, I did not find any
information of Ryckeat-Bellemans Potential parameters in the ffbonded.itp
of Charmm27 or Charmm36. I assume Charmm36 is the most updated one and the
best to be used. Do I need to consider the R-B potential or Charmm already
taking care of it by the multiplicity?

Thanks in advance!

Best!
Xueming