[gmx-users] Re: rlist cutoff question

[Pim Schravendijk]

If you have a 10 A cutoff for vdw combined with an rlist of 14 A this 
should be good enough in most cases. The distance of half the smallest 
vector is only a technical point if your box size is very small 
(interactions between a molecule and its mirror image in the neighbouring 
box should not be calculated).

Calculating coulomb using just a cutoff is mostly not a very good idea, 
PME is a better idea or if that is not an option you could try 
reaction-field.

> From: "4tejender" <4tejender at indiatimes.com>
> Subject: [gmx-users] rlist cutoff question
> 
> dear users
>  what is optimal value of rlist and cut-off for columb and vdw i should
>  use. If i have a simulation box of size 61.54,62.50,145.66 as suggested
>  in manual it should be half of the smallest vector but it will come out
>  to 0.31.Isn't it too large
>   for diffusion studies which is more preffered either Stocastic
>   dyanamics or brownian dyanamics.
> 
> thanks teje


--
Pim Schravendijk - PhD Student
Max Planck Institute for Polymer Research
http://www.mpip-mainz.mpg.de/~schraven/