GROMACS version: 2020.4
GROMACS modification: No
According to the manual, the way OPLS implements the 4-term Fourier function is as follows:
but this equation specifies nothing about the form of the 5-term Fourier dihedral function.
In addition, the manual also states that the implementation of the Fourier dihedral in the topology file is
Thus, if we stick with the convention laid out in the table above for the topology file (C1, C2, C3, C4, and C5) what is the form of the 5-term Fourier dihedral given that it is not specified in the manual? Is it the form
Any help would be greatly appreciated.