Boundary Condition

Hi. In my simulation I am trying to deposit Hydrogen on Silicon atoms from ‘Z’ direction and then apply electric field from ‘X’ or ‘Y’ direction. Firstly, I specified the boundary as ‘p p f’ to deposit H from Z direction. However, later I cannot apply electric field from ‘X’ or ‘Y’ direction as the boundary needs to be fixed to apply efield. Is there any way to change the boundary condition before applying field in the middle of the simulation? Or any other way to achieve my target here?

The question rather is, how do you propose to handle the “jump” in the electric field?

A periodic boundary means, that the system is invariant to translation, but by applying an electric field you will violate that property and there will be an unphysical discontinuity at the box boundary.