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

[Anton Feenstra]

Hi Erik, David and/or Berk,


Since Li and I can't seem to agree on what the parameters mean, and
although I'm pretty sure my explanation is correct, could one of you
set us straight here?


Li Dawei wrote:

> Hi, Dear Anton:
> 
> 
> <<No. Forces for distances up to rvdw and rcoul are evaluated each
> nstlist steps, and these forces are used till the next <<update (nstlist
> steps later). Forces for distanes < rlist are evaluated each step.
> 
> If I am right, the neighbor list stored all pairs with the distance less
> than rvdm or rcoul. However, in each step, only pairs whose distances
> are less than rlist will be re-calculated. This is the so called
> twin-cutoff method.
> 
> <<I wouldn't be surprized if the manual and the code for shift
> disagree... IIRC, this has been discussed before on the <<list, have you
> searched for this?
> 
> So in v3.2, this has been solved. And now the rlist is actually the
> neighbor list search cutoff, means rlist=rvdm+shell, rcdm and rcoul are
> the real cut-off. This is the common method that MD simulation use.


-- 
Groetjes,

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