[lammps-users] loop on parameters list

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1

Hi,
I could use some help on the following problem.
I would like to calculate, only using commands like "variable" and
"compute", the translational order parameter (Allen and Tildesley, Sect. 5.7.3).
This is simple, for a single wave vector Q=2*pi/L(mx,my,mz):

variable qmin equal 2.0*3.1415926535898/lx
variable mx equal 1.0
variable my equal 0.0
variable mz equal 0.0
variable transl atom cos(v_qmin*(v_mx*x[]+v_my*y[]+v_mz*z[]))/atoms
compute re all reduce sum v_transl

How could I efficiently loop on a list of different (mx,my,mz)?
Thanks for your help,

2

The doc page for the next command shows how to setup
double loops in your input script. You could extend it to triple
loops. But you'd probably be better off writing your own per-atom
compute that calculates this quantity. It's not hard to do, using
a per-atom compute like ke/atom as a starting point.

Steve