tip3p   TIP3P       TIP 3-point, recommended
tip4p   TIP4P       TIP 4-point
tip4pew TIP4P-Ew    TIP 4-point optimized with Ewald
tips3p  TIPS3P      CHARMM TIP 3-point with LJ on H's (note: twice as slow in GROMACS)
spc     SPC         simple point charge
spce    SPC/E       extended simple point charge
