bond_style mm3 command¶
bond_style mm3 bond_coeff 1 100.0 107.0
The mm3 bond style uses the potential that is anharmonic in the bond as defined in (Allinger)
where \(r_0\) is the equilibrium value of the bond, and \(K\) is a prefactor. The anharmonic prefactors have units angstrom^(-n): -2.55 angstrom^(-1) and (7/12)2.55^2 angstrom^(-2). The code takes care of the necessary unit conversion for these factors internally. Note that the MM3 papers contains an error in Eq (1): (7/12)2.55 should be replaced with (7/12)2.55^2
This bond style can only be used if LAMMPS was built with the YAFF package. See the Build package doc page for more info.
(Allinger) Allinger, Yuh, Lii, JACS, 111(23), 8551-8566 (1989),