[ moleculetype ] ; molname nrexcl SOL 2 [ atoms ] ; id at-type res-nr res-name at-name cg-nr charge mass 1 OW 1 SOL OW1 1 0.000 15.9994 2 HW 1 SOL HW1 1 0.527 1.0079 3 HW 1 SOL HW2 1 0.527 1.0079 4 MW 1 SOL MW1 1 -1.054 0.0000 [ settles ] ; i funct doh dhh 1 1 0.09572 0.15139 [ virtual_sites3 ] ; Vsite from funct a b 4 1 2 3 1 0.089608 0.089608 [ exclusions ] 1 2 3 4 2 1 3 4 3 1 2 4 4 1 2 3