[gmx-users] Rychaert-Belleman's dihedral

[Rongliang Wu]

hello all,
 i'm using the opls force field to simulate a system of molecules with benzene ring, i found the default dihedral fun is 3(Rychaert-Belleman's dihedral), and do i have to add those dihedrals in the benzene to the [ impropers ] so as to insure the atoms are in a plane? or can the "fun 3" keep the stoms of the benzene within the plane? is it necessary to use Rychaert-Belleman's dihedral for the oplsaa force filed?

Regards! 
 				
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Rongliang Wu
2006-03-14