Water Models

NAMD currently supports the 3-site TIP3P water model, the 4-site TIP4P water model, and the 5-site SWM4-NDP water model (from the Drude force field) [44]. TIP3P is the current default water model. Usage of alternative water models is described below.

• waterModel $<$ using which water model? $>$
  Acceptable Values: tip3, tip4, swm4
  Default Value: tip3
  Description: Specifies the water model to be used. When using the TIP3P water model, the ordering of atoms within each TIP3P water molecule must be oxygen, hydrogen, hydrogen. When using the TIP4P water model, the ordering of atoms within each TIP4P water molecule must be oxygen, hydrogen, hydrogen, lone pair. When using the SWM4-NDP water model, the ordering of atoms within each SWM4-NDP water molecule must be oxygen, Drude particle, lone pair, hydrogen, hydrogen. Alternative orderings will fail.