[gmx-users] Can't observe ion separation under the influence of electric field

[Live King]

Dear all,

I am running a simple test case with a lipid bilayer (DMPC), water, and
ions (150mM KCL) under the influence of a constant electric field ( 300mV,
500mV, and 700mV). *I expected positive and negative ions to separate in
the presence of an external electric field*. However, I am not observing
such behavior despite running the all-atom simulation for 400ns in any
case. I am using gromacs 2018.2, my mdp file is standard charmm-gui
production with electric field option.

for example 500mV electric field in Z-direction :
electric-field-z =      0.060  0     0     0 ; *500**mv  = 8.25nm* 0.060 =
500 mV *


Are there any settings to run the electric field simulation that I miss?
Any help will be greatly appreciated.


Thank you,