[Wannier] DOS and conductance calculations in W90

[Nicola Marzari]

Sumanta Bhandary wrote:
> Dear Wannier90 users,
>                      I want to know how Density of states are  
> calculated in wannier90 and how does it depend on frozen window.
> Also, is it possible to calculate the conductance and DOS for the full  
> energy spectrum even when the inner window is set up to Fermi level ?


The algorithms are those of Nardelli PRB 99, Calzolari Marzari Souza
Nardelli PRB 2004, Lee, Nardelli, Marzari PRL 2005 .

The DOS and conductance (let's think at a bulk system for the time
being) will be those described by the WFs you have identified - if those
reproduce the band structure of your system well or not above the inner
window will depend on your system, on your choice of WFs, etc.

Even below the inner window you can do a poor job in interpolating the 
band structure at k-points in between those you actually used in your
Wannier calculation - a good study case would be a semiconducting CNT,
using only the occupied subspace. The WFs interpolation would be quite
poor, unless you were to disentanble the entire pi manifold.

Have a close look at the PRL mentioned above.

			nic

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