I have carried out the band structure calculations but I don't know how to proceed with DOS calculations. Any insight or links that I can read in order to carry out this calculation would be highly valued!!
Dear Hepsibah,
I assume you use an existing package and have already the bandstructure. At that point is doesn't matter how you got your bandstructure, E(k). To determine the density of states is just a consequent step requiring only that E(k) you have already. What you have to know is that each volume element 4 pi^3/V in your Brillouin zone contains exactly 1 state (spin degeneracy already accounted for). The basic definition of the density of states D(E) = dN/(dE dV), where dN is the number of states in the interval defined by dE and dV. There are several numerical schemes to obtain the DOS D(E): A simple one is a Monte Carlo procedure. More precise are schemes like Gilat-Raubenheimer or the Lehmann tetraeder method. I am not familiar with modern packages like Quantum Espresso, but I would be surprised if it does not have the option to do the density of states calculation. Perhaps a good idea to check the manual?
Kind Regards, Chris Wijers
Hi Professor! I got confused since I had referred a lot of websites. They do scf followed by nscf wannier, pw2wannier and post processing etc.2nd one is scf followed by nscf then dos.x. nscf calculations are not supported when we make use of hybrid functionals. I also read about projwfc. So I am not sure of which procedure has to be followed. Quantum espresso supports all types of electronic structure calculations but I am not sure of which route has to be followed in order to obtain Density Of States using HSE06. Can you kindly provide me insights on the same.
Regards,
Hepsibah.C
Dear Hepsibah,
I am already sometime retired and not familiar with the abundance of electronic structure packages being around nowadays. So, for details how to handle the package, you are using now, I cannot offer specific help. However: keep in mind an electronic structure package does nothing else but solving essentially a one particle Schrodinger problem. To determine a DOS is something happening after that and does not depend on any of the details you mention. This part of the procedure has been solved already ages ago and it should be standard.
Kind regards, Chris Wijers
Thank you so much Professor! I will read through again and try it out!
Regards,
Hepsibah.C
&PROJWFC
prefix="Ag2O"
outdir='./TMP_DIR2/',
ngauss=0
degauss=0.0002
Emin=-20.0
Emax=20.0
DeltaE=0.01
filpdos="1-pdos"
/
After SCF calculation there is a package call projwfc.x for PDOS and dos.x for DOS. This input can be followed. The outdir should be same as the one in SCF calculation.
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