[Wien] Requesting help regarding WSHIFT parameter. Guidebook is not helping much.

Peter Blaha peter.blaha at tuwien.ac.at
Mon Jul 22 09:47:07 CEST 2024


Only the option with the "energy dependent" broadening needs WSHIFT.
It is used to shift the energy, where the broadening starts.
Consider an insulator: You have the VBM (EF), but you don't want to set 
EF as begin of the E-broadening, but eventually, you want to set it to 
the CBM (or even a bit higher).
Why would one use an E-dependent broadening: ??
If you excite an electron to a state just above EF, you can assume that 
it "lives long" (small broadening), but an electron excited to a very 
high energy state probably stays only very short time there (large 
broadening).

Obviously, since the gap is different for different compounds, also your 
WSHIFT should be different.

In any case, in my opinion, "playing with broadening" is more or less 
valid to get good agreement with experiment.



Am 17.07.2024 um 11:31 schrieb Pranjal Nandi:
> Dear All,
> 
> Hello.
> 
> Wien2k version 23.2.
> 
> I am unable to understand what is meant by WSHIFT: edge offset as 
> mentioned in the guidebook against the file case.inb (pg 177)
> 
> The reason why I am asking is that I would like to compare 4-5 
> structure’s case.broadspec file (the structures are similar, just with 
> different charged states). If I understand correctly, for a proper 
> comparison, I should use the same broadening for the elnes file.
> 
> But I have observed that for each case, the system automatically 
> generates a case.inb file with only the WSHIFT varying in each and I wonder
> 
>  1. how this parameter affects the broadening (and if I should keep it
>     constant for all my 4-5 cases)
>  2. How does the programme by default assigns a value
>  3. How do I understand what parameter to set considering that it keeps
>     changing for each case
> 
> I couldn’t find any further description about it in the guidebook.
> 
> A guidance regarding the same would be very helpful.
> 
> Thank you in advance.
> 
> With warm regards,
> 
> Pranjal
> 
> 
> 
> Aquest missatge, i els fitxers adjunts que hi pugui haver, pot contenir 
> informació confidencial o protegida legalment i s’adreça exclusivament a 
> la persona o entitat destinatària. Si no consteu com a destinatari final 
> o no teniu l’encàrrec de rebre’l, no esteu autoritzat a llegir-lo, 
> retenir-lo, modificar-lo, distribuir-lo, copiar-lo ni a revelar-ne el 
> contingut. Si l’heu rebut per error, informeu-ne el remitent i elimineu 
> del sistema tant el missatge com els fitxers adjunts que hi pugui haver.
> 
> Este mensaje, y los ficheros adjuntos que pueda incluir, puede contener 
> información confidencial o legalmente protegida y está exclusivamente 
> dirigido a la persona o entidad destinataria. Si usted no consta como 
> destinatario final ni es la persona encargada de recibirlo, no está 
> autorizado a leerlo, retenerlo, modificarlo, distribuirlo o copiarlo, ni 
> a revelar su contenido. Si lo ha recibido por error, informe de ello al 
> remitente y elimine del sistema tanto el mensaje como los ficheros 
> adjuntos que pueda contener.
> 
> This email message and any attachments it carries may contain 
> confidential or legally protected material and are intended solely for 
> the individual or organization to whom they are addressed. If you are 
> not the intended recipient of this message or the person responsible for 
> processing it, then you are not authorized to read, save, modify, send, 
> copy or disclose any part of it. If you have received the message by 
> mistake, please inform the sender of this and eliminate the message and 
> any attachments it carries from your account.
> 
> 
> _______________________________________________
> Wien mailing list
> Wien at 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

-- 
-----------------------------------------------------------------------
Peter Blaha,  Inst. f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-158801165300
Email: peter.blaha at tuwien.ac.at
WWW:   http://www.imc.tuwien.ac.at      WIEN2k: http://www.wien2k.at
-------------------------------------------------------------------------


More information about the Wien mailing list