[Wien] Checking the effect of pressure on the bandstructure

[Fecher, Gerhard]

Hi Amit
You may calculate the single crystal elastic constants (sub-programs and scripts are available in Wien2k) to find out how the lattice parameters change under pressure.
If you apply pressure along some axis c, the remaining two axes a and b will also change, usually become larger, only in few cases they may shrink also with the pressure.
(Indeed, you can also check for changes in the lattice under shear or combinations of different mechanical stress)
Might be good to have some exprimental data of the material to check if the changes of the lattice under uniaxial pressure is correctly described.

If you have the new lattice parameters you can calculate the spaghetties as usual.

Temperature is bad, it will force occupation of phonons that cause an energy dissipation of the electrons.
This is , as far as I know, not implemented in Wien2k (maybe it is in some Greens function codes that allow for complex potentials with an imaginary part to simmulate the energy dissipation).
It will smear out the spaghettis.

Ciao
Gerhard

DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
"I think the problem, to be quite honest with you,
is that you have never actually known what the question is."

====================================
Dr. Gerhard H. Fecher
Institut of Inorganic and Analytical Chemistry
Johannes Gutenberg - University
55099 Mainz
and
Max Planck Institute for Chemical Physics of Solids
01187 Dresden
________________________________________
Von: wien-bounces at zeus.theochem.tuwien.ac.at [wien-bounces at zeus.theochem.tuwien.ac.at] im Auftrag von amit ribak [amit.ribak at gmail.com]
Gesendet: Donnerstag, 7. Mai 2015 09:01
An: wien at zeus.theochem.tuwien.ac.at
Betreff: [Wien] Checking the effect of pressure on the bandstructure

​Hello,

I'm interested in checking the effect of pressure (uni-axial) on the band structure. I first calculated the band structure with and without spin-orbit interaction and was able to restore previous results.
Now, I want to see how the pressure affects the band structure. How can I incorporate this into Wien2k?

The c over a optimization is the way to do it or I simply need to change the lattice parameters of the initial structure?

Best regards,
Amit