Thank you very much for you response.
i am getting tired of having to explain the same things over and over
again, and you not getting the point.
if you want to have the system adjust to reach a target pressure and also
have immobile plates, you *must* allow the distance between the plates to
vary as you vary the box dimensions. if you apply dilation only to the
water atoms, they will be pushed towards or even "through" the plates, if
you don't allow any atoms to dilate but only the box length to change, it
will not have much of an effect, since your water confinement doesn't
change. if you want to keep a fixed distance between the plates, and the
system to adjust to pressure, you have to either allow dilation in x and y
direction. if you want to keep the plates fixed and no variation of the box
in x and y, you cannot adjust the system to the pressure except for
changing your original geometry/density and then run with fix nvt.
technically, you might try a grand canonical ensemble, but since you are
struggling with the physics as it is, i don't recommend it, since that will
be significantly more challenging to get right.
as indicated above, i have no more interest to follow up on this, so this
is my last response on this subject. you'll need to find somebody else to
My current study system not totally the same with the system of that
paper.Also, the author did not reply me yet.However,I also need consider
the plates as rigid body.
it makes even less sense to apply fix rigid to those plates, specifically
not with a thermostat applied, when at the same time you want those plates
to remain in place. it is also incorrect to apply multiple time integrators
(fix move counts as one). again, simply do not time integrate those
particles and they'll behave properly. if that doesn't work for you, there
must be other mistakes.
Briefly say,I just want to adjust commands to solve the problem show below
First one is taht snapshot (add pbc along x and y )with NVT,the pbc along
x y have not broken(top figure).The second is snapshot under NPT
.However, the pbc along x y direction have been broken(middle figure),since
the box length were changed under NPT.
no, your interpretation must be wrong. this must be due to bad initial box
dimensions or incorrect geometries. you are coupling fix npt only to the z
direction, so x and y are not changed. this one can easily see by looking
at dump files and/or outputting box lengths.
*I wonder that there is any method can control system with NPT which
result in non-broken x y direction boundary (means no change on x y box
it is not a problem of fix npt. it is a problem of your input. ...and a
apparently a case of PEBCAC as well.