[QE-users] Can QE project selected electronic states of selected atoms into the k-space?

Sun Aug 28 13:26:02 CEST 2022

> Let me  be clear. My question actually is "Can QE  project selected electronic 
states of selected atoms into the first Brillouin Zone?"

Dear Jibao,
if you come from a quantum chemistry background, or if you have only 
ever used localized basis-set codes (gaussian, siesta,... ) you expect 
to be able to assign a wavefunction to an atom. But Quantum ESPRESSO 
(like VASP, Abinit,... ) is a plane-waves basis code, where it is very 
clear that valence electrons cannot be assigned to a specific atom, they 
are all infinitely delocalized in real space (but to some extent 
localized in reciprocal space).

I guess the answer is "no". Quantum ESPRESSO cannot do what you ask.

In order to help intuition, people using plane waves sometimes do the 
opposite: transformdelocalized crystal wavefunction into real space 
functions in order to associate electronic bands with their chemical 
"character". This can be done dirty and quick with projwfc using atomic 
wavefunctions, or properly and not so easy with Wannier functions.

kind regards

On 28/08/2022 12:57, Jibiao Li wrote:
> Dear Lorenzo
>
> Let me be clear. My question actually is "Can QE  project selected 
> electronic states of selected atoms into the first Brillouin Zone?"
>
> Best
> ------------------------------------------------------------------------
>
> Jibiao Li
>
> Department of Materials Science and Engineering
>
> Yangtze Normal University
>
> Juxian Avenue 16, Fuling, Chongqing, China 408100
>
> Scopus Research ID: 54944118000 
> <https://www.scopus.com/authid/detail.uri?authorId=54944118000>
>
> Web of Science Research ID: F-1905-2016 
> <https://publons.com/researcher/2283103/jibiao-li/>
>
>
>
>
> ------------------ Original ------------------
> *From:* "Quantum ESPRESSO users Forum" <lorenzo.paulatto at cnrs.fr>;
> *Date:* Sun, Aug 28, 2022 06:51 PM
> *To:* "users"<users at lists.quantum-espresso.org>;
> *Subject:* Re: [QE-users] Can QE project selected electronic states of 
> selected atoms into the k-space?
>
> I guess projwfc with option kresolveddos can project Bloch 
> wavefunction of a selected k-point onto atomic reference (i.e. 
> arbitrary) wavefunctions. I'm not sure that it is what you want.
>
> > Clearly wave-functions are things in the real space not the momentum 
> space.
>
> Would you mind explaining? It is not clear to me that Bloch 
> wavefunctions are real space objects. Wannier functions are clearly 
> real space, but they are clearly not "wavefunctions" (i.e. they are 
> not stationary states of the crystal Hamiltonian).
>
> cheers
>
> On 28/08/2022 12:43, Jibiao Li wrote:
>>
>> Dear Lorenzo,
>>
>> Thank you for your reply, but my question is "Can QEproject selected 
>> electronic states of selected atoms into the momentum space?" Clearly 
>> wave-functions are things in the real space not the momentum space.
>>
>> Regards
>> ------------------------------------------------------------------------
>>
>> Jibiao Li
>>
>> Department of Materials Science and Engineering
>>
>> Yangtze Normal University
>>
>> Juxian Avenue 16, Fuling, Chongqing, China 408100
>>
>> Scopus Research ID: 54944118000 
>> <https://www.scopus.com/authid/detail.uri?authorId=54944118000>
>>
>> Web of Science Research ID: F-1905-2016 
>> <https://publons.com/researcher/2283103/jibiao-li/>
>>
>>
>>
>>
>> ------------------ Original ------------------
>> *From:* "Quantum ESPRESSO users Forum" <lorenzo.paulatto at cnrs.fr>;
>> *Date:* Sun, Aug 28, 2022 06:24 PM
>> *To:* "users"<users at lists.quantum-espresso.org>;
>> *Subject:* Re: [QE-users] Can QE project selected electronic states 
>> of selected atoms into the k-space?
>>
>> Dear Jibiao,
>>
>> I'm not sure if I understand your question. Quantum ESPRESSO can and 
>> does compute wavefunctions and Kohn-Sham energy bands at given 
>> k-points. It is actually the main thing it does.
>>
>> kind regards
>>
>>
>> On 28/08/2022 12:13, Jibiao Li wrote:
>>> Dear All,
>>>
>>> In condensed matter physics, projecting electronic states of 
>>> targeted atoms into the momentum space is definitely an important 
>>> tool to study electronic structures of materials. I am writing this 
>>> short email to get answer whether QE has the functionality to do 
>>> like this.
>>> May I  project either all or selected electronic states of selected 
>>> atoms into the k-space in QE?
>>>
>>> Regards
>>>
>>> Jibiao Li
>>>
>>> Department of Materials Science and Engineering
>>>
>>> Yangtze Normal University
>>>
>>> Juxian Avenue 16, Fuling, Chongqing, China 408100
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> Jibiao Li
>>>
>>> Department of Materials Science and Engineering
>>>
>>> Yangtze Normal University
>>>
>>> Juxian Avenue 16, Fuling, Chongqing, China 408100
>>>
>>> Scopus Research ID: 54944118000 
>>> <https://www.scopus.com/authid/detail.uri?authorId=54944118000>
>>>
>>> Web of Science Research ID: F-1905-2016 
>>> <https://publons.com/researcher/2283103/jibiao-li/>
>>>
>>>
>>>
>>> _______________________________________________
>>> The Quantum ESPRESSO community stands by the Ukrainian
>>> people and expresses its concerns about the devastating
>>> effects that the Russian military offensive has on their
>>> country and on the free and peaceful scientific, cultural,
>>> and economic cooperation amongst peoples
>>> _______________________________________________
>>> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
>>> users mailing listusers at lists.quantum-espresso.org
>>> https://lists.quantum-espresso.org/mailman/listinfo/users
>> -- 
>> Dr. Lorenzo Paulatto
>> IdR @ IMPMC - CNRS UMR 7590 & Sorbonne Université
>> phone: +33 (0)1 442 79822 / skype: paulatz
>> http://www.impmc.upmc.fr/~paulatto/ - https://anharmonic.github.io/
>> 23-24/423 B115, 4 place Jussieu 75252 Paris CX 05
>>
>> _______________________________________________
>> The Quantum ESPRESSO community stands by the Ukrainian
>> people and expresses its concerns about the devastating
>> effects that the Russian military offensive has on their
>> country and on the free and peaceful scientific, cultural,
>> and economic cooperation amongst peoples
>> _______________________________________________
>> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
>> users mailing listusers at lists.quantum-espresso.org
>> https://lists.quantum-espresso.org/mailman/listinfo/users
> -- 
> Dr. Lorenzo Paulatto
> IdR @ IMPMC - CNRS UMR 7590 & Sorbonne Université
> phone: +33 (0)1 442 79822 / skype: paulatz
> http://www.impmc.upmc.fr/~paulatto/ - https://anharmonic.github.io/
> 23-24/423 B115, 4 place Jussieu 75252 Paris CX 05
>
> _______________________________________________
> The Quantum ESPRESSO community stands by the Ukrainian
> people and expresses its concerns about the devastating
> effects that the Russian military offensive has on their
> country and on the free and peaceful scientific, cultural,
> and economic cooperation amongst peoples
> _______________________________________________
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing listusers at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users
-- 
Dr. Lorenzo Paulatto
IdR @ IMPMC - CNRS UMR 7590 & Sorbonne Université
phone: +33 (0)1 442 79822 / skype: paulatz
http://www.impmc.upmc.fr/~paulatto/ - https://anharmonic.github.io/
23-24/423 B115, 4 place Jussieu 75252 Paris CX 05
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20220828/9805a57e/attachment.html>