Dear All,

`I am interested to project WIEN2k band structure onto atomic orbitals,`

`but getting complex amplitudes. For example, for graphene Dirac band`

`(formed primarily by C 2pz) I would get two k-dependent complex numbers`

`A_C2pz(k) and B_C2pz(k), where A and B are the two inequivalent sites,`

`and these coefficients for other orbitals (near the Dirac points) would`

`be nearly zero. Of course, for graphene I can write a TB model and get`

`these numbers, but already for WSe2 monolayer TB model has several bands`

`(TB models for WSe2 are published but implementing would be`

`time-consuming), and for a generic material there is often no simple TB`

`model.`

`Some time ago I looked at the WIEN2k wave functions, but because of the`

`way LAPW works, it is not a trivial task to project these onto atomic`

`orbitals. This is due to the radial wave functions, each one receiving`

`its own coefficient.`

`I was wondering if I can somehow get such projection automatically using`

`Wien2Wannier, and later with some Wannier program. I thought it is good`

`to ask before I invest any time into this.`

`And I would need it with spin, because I am interested with systems`

`where SOC plays a role.`

The reason I ask:

`Simple model of photoemission can be made by assuming coherent addition`

`of atomic-like photoionization, with additional k-dependent initial band`

`amplitudes/phases. One can assume that radial integrals in photoemission`

`matrix elements don't have special structure and maybe just take atomic`

`cross sections of Yeh-Lindau. But one still needs these complex`

`coefficients to allow for interference of the emission from different`

`sites within the unit cell. I think for a relatively simple material`

`such as WSe2 monolayer, the qualitative result of this might be`

`reasonable. I am not aiming at anything quantitative since we have`

`one-step-model codes for quantitative.`

`Any suggestion on how to do this projection (even approximately) within`

`the realm of WIEN2k would be welcome.`

Best, Lukasz PD Dr. Lukasz Plucinski Group Leader, FZJ PGI-6 Phone: +49 2461 61 6684 https://electronic-structure.fz-juelich.de/ _______________________________________________ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html