[Pw_forum] cohesive energy of tungsten

[Gabriele Sclauzero]

On 12/17/2010 06:47 AM, vicky singh wrote:
> sorry for late reply. so what is your suggestion for getting the 
> accurate value for cohesive energy for W. I also tried another BCC 
> material Ta and its cohesive energy is also more than 22% higher than 
> the reported value (kittel). 

Which kind of value? Is it from experimental results, from HF, DFT, or 
more sophisticated calculations? Have you tried bcc iron,
  for instance? I think that for this material you would be able to find 
many DFT results to compare with in the literature.
In order to get a well converged value there are many critical points to 
take care of in the calculation, especially that for the atom. There has 
been several discussions about that in the last month on the forum, and 
for sure many others earlier. Please take a few minutes to browse the 
archives.


GS

> But when i calculated the cohesive energy for FCC Ni and Al the 
> difference from experimental result is around 6 % (on the higher side)
>
>  Thanks in advance
>
> Vicky singh
> Bangalore
-- 

Gabriele Sclauzero, EPFL SB ITP CSEA
PH H2 462, Station 3, CH-1015 Lausanne