In non magnetic materials, is the lowest energy configuration and not SIA dumbbell. But, in bcc Iron dumbbell is the lowest energy configuration. What makes dumbbell in bcc Iron get to the lower energy than dumbbell. why ?
Mr. Arumugakani,
This depends on the disposition of the different type atoms in the crystal.
Hi Kedharnath,
It arises due to the magnetic properties of Fe which for context supports antiferromagnetism in the fcc phase and ferromagnetism in the bcc.
For an SIA in the bcc phase of Fe, magnetism in the core of the defect lowers the energy of the dumbbell by ~0.7 eV relative to the crowdion, which is observed in other non-magnetic bcc materials. This is simply why it is more stable.
I would recommend the following papers for further details:
C.-C. Fu, F. Willaime & P. Ordejon, Phys. Rev. Lett. 92, 094418 (2004)
D. Nguyen-Manh, A. P. Horsfield & . S. L. Dudarev, Phys. Rev. B 73, 020101(R) (2006)
P. Olsson, C. Domain & J. Wallenius, Phys. Rev. B 75, 014100 (2007)
Hope this helps.
Jacob
Dear Jacob Chapman
Thank you for your answer. That was helpful and added clarity.
I also read ( Sorry, I don't remember the article) that even Ar 4s1 3d7 and Mg 3p6 4s1 3d7 electronic configurations of Fe shows little difference in energy of dumbbell.
- Badges
- Science topic