it seems to me that I found a bug connected with fix langevin and fix_modify.
It is written in the manual about the langevin fix that "the way that
temperature is computed by this fix can be changed by using the fix_modify
command". But the sample script (see below) results in the message 'ERROR:
Illegal fix_modify command'. Similar error holds for the 17Jan05 and for the
latest 12Apr06 version.
(If I change the langevin fix to the temp/rescale fix than everything works fine.)
At the same time, in the fix_modify man-page it is not written that fix_modify
can be applied to fix langevin. Where is the mistake?
Any comments will be greatly appreciated!
boundary p p p
lattice fcc 0.905
region box block 0.0 5.0 0.0 5.0 0.0 5.0
region heatedr block 0.0 5.0 0.0 5.0 0.0 2.0
create_box 1 box
create_atoms 1 box
mass 1 1.0
group heated region heatedr
temperature heated_T heated full
pair_style lj/cut 2.5
pair_coeff 1 1 1.0 1.0 2.5
velocity all create 0.8 5812775 mom yes rot yes dist gaussian
fix 1 all nve
fix 2 heated langevin 0.8 0.8 10.0 87263
#fix 2 heated temp/rescale 10 0.8 0.8 0.02 1.0
fix_modify 2 temp heated_T