Internal QM/MM

QM/MM calculations can be carried out in several different ways with TeraChem. The internal QM/MM code supports only water molecules in the MM region. Parameters given here are relevant for this code. Note that alternative QM/MM methods are much more flexible, for example using OpenMM for the MM region or using Amber to drive TeraChem.

Parameter	Description	Default Value
qmmm	Name of file containing MM water coordinates. The presence of this keyword triggers a QM/MM calculation using TeraChem's internal MM water code.	not set
water	tip3p|spc|spc/e|tip4p|swm4|swm4-dp|swm4-ndp Type of water molecules used for QM/MM with TeraChem's internal MM water code	tip3p
rigidbonds	yes|no|true|false Should the O-H bonds be kept rigid?	true