The ABINIT Users Mailing List ( CLOSED )

[Scott Beckman <spbeckman@gmail.com>]

Hi,

If the two procedures result in two different structures then you may  
be accidentally forcing one of the calculations into a high symmetry  
solution.

I'd suggest that you compare both the energy difference between the  
two structures as well as the symmetry.

On Jan 8, 2008, at 4:13 AM, hyello25@gmail.com wrote:

> Dear Abinit users:
>   Another question confused me fo ra long time. May need your help  
> again.
>   When I do the cell optimizetion, I first modify nuclear position 
> (optcell=0), then do full optimization of cell geometry(optcell=2).  
> Is it right?
>   And if dont't use optcell=2(full optimization of cell geometry),  
> after I modify nuclear position(optcell=0), for optimization of  
> volume only(optcell=1) and constant-volume optimizationof cell  
> geometry(optcell=3), which one I should do first? (I try both, the  
> results are different. )
>
>   Best Regards,
>
>
> !-----------------------!
> G.R Qian
> Physics Dept. NJU CN
> !------------------------!