[Pw_forum] Re : something strange in rutile and anatase calculation

[Virginie Trinite]

Hi,

We have observed that including or not semi-core states in the 
pseudopotential af Ti, can make great difference in the stabilisation of 
\alpha versus \omega phases of Ti and also for anatase and rutile phase 
( For Ti, you can look at Journal of Physics C, vol 20, 235239 (2008)).
I am very interest of the reference of the  free energy calculations 
showing  the  stabilization of \alpha-Ti by phonons (We have made a 
approximate evaluation of this contribution and our conclusion was that 
it was not sufficient).

Bests

----------------------------------------
PhD Trinite Virginie
Physics Research Group of Thales Research & Technology


2008/8/28, Eyvaz Isaev <eyvaz_isaev at yahoo.com>:
 >Hi,
 >
 >One more suggestion.
 >As far as I know the same situation is for \alpha and \omega phases of 
Ti, as well as HCP and DHCP phases of FeH. But free energy calculations 
have shown than \alpha-Ti  and DHCP FeH are >stabilized due to the 
phonon contribution.
 >For FeH you can see: Eyvaz I. Isaev et al., Dynamical stability of 
Fe-H in the Earth's mantle and core regions, Proceedings of the National 
Academy of Sciences of the USA (PNAS), 104 (22), 29 May >2007, 9168. 
PNAS Special Issue "Geophysics".
 >
 >So, you can try follow this way, if you like.
 >
 >Bests,
 >Eyvaz.