Hi ,
I am trying to simulate a system where I want to study interaction of sulfides with graphene. The sulfide particles are negatively charged and hence to maintain charge neutrality of the system, I have introduced necessary amounts of counter ions in between the two graphene sheets. So I have a system which is layerd as below:
First sulfide and a solvent layer
Graphene sheet
solvent layer with counterions
Graphene sheet
Second sulfide with solvent layer
When I try to run the simulations, there are long range electrostatic interactions between sulfides and counterions which leads to sulfide being attracted towards the susbtrate. I dont want the counterions to have any influence on the movement of sulfide paricles. Is there any way in which I can switch off the long range interactions. The solvents that I am using are polar in nature. Do I need to use long range electrostatic interactions for such a situation ? The only reason I am introducing the counterions is to make the system charge neutral, since it is not advisable to run MD with net negative charge which is around -116.
Kindly help me with this matter.
Regards,
Hi ,
I am trying to simulate a system where I want to study interaction of
sulfides with graphene. The sulfide particles are negatively charged and
hence to maintain charge neutrality of the system, I have introduced
necessary amounts of counter ions in between the two graphene sheets. So I
have a system which is layerd as below:
First sulfide and a solvent layer
Graphene sheet
solvent layer with counterions
Graphene sheet
Second sulfide with solvent layer
When I try to run the simulations, there are long range electrostatic
interactions between sulfides and counterions which leads to sulfide being
attracted towards the susbtrate. I dont want the counterions to have any
influence on the movement of sulfide paricles. Is there any way in which I
can switch off the long range interactions. The solvents that I am using are
polar in nature. Do I need to use long range electrostatic interactions for
such a situation ? The only reason I am introducing the counterions is to
make the system charge neutral, since it is not advisable to run MD with net
negative charge which is around -116.
you need to make the solvent region large enough (and that usually
means *much* larger than you might think), and then can use a
confinement (e.g. a wall/harmonic) to restrict where the counter ions
go. this principle is used in bio simulations for voltage gated ion
channels.
check out the work of this guy,
https://scholar.google.it/citations?user=mR954cMAAAAJ&hl=en
it might help in identifying a strategy that is applicable to your case.
axel.
Thanks a lot for your kind help.
Regards,
Aniruddha M Dive
PhD student
School of Mechanical and Materials Engg.
Washington State University