Hello,
I have successfully managed to run a MEAM equilibration run at 1900K on a particle consisting of about 2000 Ni atoms, and save out a restart file at the end of the simulation.
I now want to combine this set of equilibrated atoms with their associated velocities, together with another set of atoms (a slab of nickel, separately equilibrated at 300K).
Setting aside for a minute the problem of loading two independently produced restart files into the same simulation (which would presumably be best run as NVE), I want to give the particle an initial centre-of-mass velocity towards the slab.
How can I do this? The 'velocity' options seem to allow setting a constant velocity, or random velocities characteristic of a specific temperature (overwriting the equilibrated data), but not both, and there does not appear to be an obvious 'add' option.
Advice is also welcome on the 'two-into-one' problem mentioned above.
Many thanks in advance,
Steve Kirk
Hello,
hi steve,
I have successfully managed to run a MEAM equilibration run at 1900K on
a particle consisting of about 2000 Ni atoms, and save out a restart
file at the end of the simulation.
I now want to combine this set of equilibrated atoms with their
associated velocities, together with another set of atoms (a slab of
nickel, separately equilibrated at 300K).
Setting aside for a minute the problem of loading two independently
produced restart files into the same simulation (which would presumably
be best run as NVE), I want to give the particle an initial
centre-of-mass velocity towards the slab.
How can I do this? The 'velocity' options seem to allow setting a
i think the direct solution to both your problems would be to use
restart2data to create two data files and then merge those two
manually with a text editor. the data file contains also a Velocities
field and so you can just add a constant velocity to the respective
particles with a show awk/perl/python/whatever script.
i've set up a similar kind of simulation (hydrogen molecule "shot" onto
an ultra thin gold foil) in a similar style with a quantum chemistry
code several years ago.
constant velocity, or random velocities characteristic of a specific
temperature (overwriting the equilibrated data), but not both, and there
does not appear to be an obvious 'add' option.
granted, that might be useful to implement.
cheers,
axel.
The velocity command has a sum yes/no option
which lets you add new velocities to existing ones.
Combining 2 restart files is best done thru a text data
file as Axel suggested.
Steve