[gmx-users] The meaning of rlist, rvdm and rcolumn

[Anton Feenstra]

Li Dawei wrote:

> Dear all:
> 
> I searched this mailing list but become even more confused. Who can help
> to clarify the exact meaning of these parameters. 

[...]

> http://www.gromacs.org/pipermail/gmx-users/2002-June/028443.html
> http://www.gromacs.org/pipermail/gmx-users/2003-January/030507.html

these links are dead...

[...]

> this implies: rlist > rvdw,rcoulomb > r*_switch
> ... in contrast to (part of) the docu, and the
> errormsg given by the code, and to one of the
> messages cited above.(the message of Anton
> Feenstra reminds me rather of another concept,
> namely the multiple timestep algoritm which, if 
> I am not mistaken, is not implemented
> in Gromacs)

Your explanation seems correct to me. rlist is the cutoff
for neighbour searching, i.e. each nstlist steps all atoms
within rlist are put in the neighborlists and forces are
evaluated. Each step, all atom pairs in the neighborlists
are checked against rvdw and rcoul and forces are evaluated
for all distances below these cutoffs.


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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