[Wien] [Wien2k User Group] Lattice stability in bcc, fcc and hcp and other crystal structures

[Ghosh SUDDHASATTWA]

Dear Wien2k users, 

We consider that the stable ground state of a metal is bcc. The fcc
structure is the high temperature phase. To calculate the enthalpy of
transformation of the fcc to bcc, we consider the following 

Enthalpy of transformation =ENE(fcc)-ENE(bcc)

 

Now for this above equation, do we have to do a geometry optimization and
then calculate the ENE? 

I guess if bcc and fcc are stable phases, then we need not do. So ENE would
be for a normal SCF calculation (with so,sp, our choice, of course) 

 

Now, for example, We want to calculate the ENE of Fe in a monoclinic
lattice, then doing a geometry optimization and then finding the ENE has a
purpose. 

What about the stable phases? And what about the high temperature phases? 

 

Any suggestions 

 

Suddhasattwa Ghosh 

 

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