[Pw_forum] Titanium atomic positions

[Hande Ustunel]

Dear Bertrand,

Your atomic positions are rather off with a large gap between rumpled Ti
layers. Perhaps you should double-check that your definition of the hcp
unit cell matches that for ibrav=4 in the code. You can find this
information in the Doc directory in your copy of espresso.

Besides, you should be able to check your structure for yourself using
xcrysden (--pwi option). 

Best wishes,
Hande

On Wed, 2 Sep 2009, Bertrand SITAMTZE wrote:

> 
> Dear all,
> 
> Titanium belongs to the 	hexagonal P63/mmc
> (n° 194) space group. I would like somebody to confirm that my attached 
> input section concerning the bravais lattice and specially the atomic positions are good.
> 
> &SYSTEM
> ibrav=4
> celldm(1)=5.576203
> celldm(3)=1.587874
> nat=2
> ntyp=1
> ecutwfc=40.0
> /
> &ELECTRONS
> diagonalization='cg'
> /
> ATOMIC_SPECIES
> Ti 47.867 Ti.pw91-nsp-van.UPF
> ATOMIC_POSITIONS
> Ti 0.3333  0.6666  0.2500
> Ti 0.6666  0.3333  0.7500
> K_POINTS automatic
> 8 8 4 0 0 0
> 
> 
> Best regards
> 
> *********************
> Bertrand SITAMTZE
> PhD student
> Department of Physics
> University of Yaoundé I-Cameroon
> ***********************
> 
> 




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