[gmx-users] Is there force field for the heavy ions?

[Mark Abraham]

G.H. Zuo wrote:
> Dear Gromacs users
> 
> I want do some studies about the As and Sn. But I can't found them in 
> the regular force field, including
> oplsaa and amber.  How can I get the parameters for these ions? Or there 
> are some method to obtain
> these parameters?

... with difficulty. See 
http://wiki.gromacs.org/index.php/Exotic_Species in the first instance.

Mark