Calculating drift velocity

Hello,

I would like to calculate the mobility of a water and ion solution. One method I would like to do this is to implement an electric field in the system and calculate the drift velocity (velocity not including the thermal velocity) of the ions. What is a good method of calculating the drift velocity? I couldn’t find any existing functions in the LAMMPS documentation to do this.

Additionally, how does the boundary conditions work when an electric field is implemented?

Thank you!

Jo

Hello,

I would like to calculate the mobility of a water and ion solution. One
method I would like to do this is to implement an electric field in the
system and calculate the drift velocity (velocity not including the thermal
velocity) of the ions. What is a good method of calculating the drift
velocity? I couldn't find any existing functions in the LAMMPS
documentation to do this.

​have a more careful look at the documentation for the variable command.
check out "vcm()"​

Additionally, how does the boundary conditions work when an electric field
is implemented?

​boundaries don't matter for the model implemented in fix efield.

axel.​