Alternative algorithm for fix bond/create

Dear lammps developers,

I have implemented an alternative partner selection algorithm for the fix
bond/create from the package MC. I have added it, in my personal repository, as
the file fix_bond_create_random.{h,cpp}
https://github.com/pdebuyl/lammps/tree/fbc_random/src/MC

This algorithm differs from the existing one in that the new bonds are formed
for partners at random within the given cutoff instead of selecting closest
partners. As a result, the polymerization kinetics is slightly different and
follow the rate equation for chain growth (as in R. L. C. Akkermans, S.
Toxvaerd and W. J. Briels, J. Chem. Phys. 109, 2929 (1998)
http://dx.doi.org/10.1063/1.476845 ).

If you are interested in integrating it, I would gladly provide example input
scripts and update the doc page. For now the code is duplicated in a separate
file but many parts of the code are identical to fix_bond_create.{h,cpp} and
depending on your feedback I could merge the features so that the user can pick
the algorithm as an option to fix bond/create.

This work is related to a pending publication http://arxiv.org/abs/1409.7498
that I started with ESPResSo++ and to which I am adding a comparison with the
LAMMPS version.

Best Regards,

Pierre de Buyl

Pierre - this seems like it would be a nice option

for fix bond/create, perhaps as a keyword option

like “select value” where value = nearest or any.

Thus it would be good if the code were integrated

into the existing fix bond/create. If the logic for

both options complicated post_integrate() too much,

there could simply be 2 functions, and post_integrate()

could call one of them.

If you could likewise update the doc page, then

send the files to me (directly, not thru the mail list),

then we can release them.

Thanks,

Steve

Dear Steve,

Thanks for your reply. I will prepare a merged fix then and edit the doc
accordingly.

Regards,

Pierre