rigid tip4p only?

Hi Lammps users,

I just want to make sure if what I’m thinking is correct.
pair_lj_cut_coul_long_tip4p and pppm_tip4p, only work for rigid water molecules, which means SHAKE method have to be applied during simulation, because the equations (eqn.(8)) of force redistribution are really derived from shape-fixed molecules. If I’m not right, pls correct me. Thanks.

Here is the reference paper info:
Title:Improving Efficiency of Large Time-Scale Molecular Dynamics Simulations of Hydrogen-Rich Systems
Journal: Journal of Computational Chemistry, Vol. 20, No. 8, 786]798 (1999)