Cell Optimization: failed to compare the lattice parameter with XRD data, how to change the setting in input?

[Jingyun Ye]

Hi, all

I met a problem which stops me to further study my system. I am doing the 
cell optimization of  MOF crystal which is a cubic structure. I always 
failed to compare my calculated lattice parameter with the experimental 
data though I try to change the setting in the input, such as increase the 
cut_off from 300 to 350, increase the EPS in QS to 10-12, in SCF to 10-7. 
The lattice from my calculation is 0.2 angstrom larger than the XRD data. 
But my VASP results is close to the experimental data. I also found other 
calculation result which is also close to the experimental result too. 
Could you please  give me some suggestions about the setting? Is there any 
setting I could try to get better data?
I will be very grateful！



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20160303/7de0895d/attachment.htm>