how to use ewald for tip4p water model?

dear all,
I want to simulate water with tip4p model with long-range Coulombic solver for big simulation box.

my ensemble is nvt. but system gives error.
ERROR: Out of range atoms - cannot compute PPPM (…/pppm_tip4p.cpp:107)

pppm/tip4p can not compute it. size of my simulation box is (1001005)

unit is real.

how to use ewald for tip4p water model ?

thanks a lot.


You can’t use ewald for tip4p. If you simulation is blowing up with PPPM it will probably blow up with Ewald too (if you could use it). Even if you could, it would be really slow.