[gmx-users] OPLSAA

[Eric Smoll]

Hello Gromacs users,

Here is a quote from a JPCB paper with over 500 citations:

"In fact, in the specification of the OPLS-AA force field, sites within the
same molecule separated by *more than* three bonds interact by
Lennard-Jones and electrostatic potentials scaled by a factor of 0.5"

Am I correct in assuming that "separated by more than three bonds" is a
typo and should "separated by three bonds"? I have read the original OPLS
reference (Jorgensen 1996) and it says:

"it was found to be necessary to scale the 1,4-nonbonded interaction to
permit use of the same parameters for inter- and intramolecular
interactions. Scaling factors fij = 1/2 for both the coulombic and
Lennard-Jones interactions emerged a  the final choice..."

There is no mention of this phrase in the additions and corrections
document.

Gromacs only scales the 1-4 interactions, not all nonbonded interactions
beyond three bonds, correct?

Best,
Eric