Re: [Wien] Spin-polarized DOS for dopants in non-magnetic materials

2019-01-21 Thread Lyudmila Dobysheva 

18.01.2019 12:33, Marcelo Barbosa :

I’m calculating the DOS for dopants in semiconductors to get the corresponding 
impurity bands.
I’m dealing with non-magnetic materials and non-magnetic dopants, so I would 
assume that no spin-polarization was needed.
However, in some cases when substituting an atom for a dopant with different 
valence number, the DOS reveals an impurity band with different contributions 
from spin-up and spin-down due to the extra/missing electron. Also, the energy 
difference from the valence band maximum to the impurity band changes from a 
non spin-polarized calculation to a spin-polarized calculation.


An example: Cu and oxygen are nonmagnetic, but some Cu oxide is magnetic 
(AFM). So, your case is not surprising for me.



My question then is: should I consider the spin-polarized results every time 
the spin-up and spin-down contributions are different? Or is there any good 
argument to choose the non spin-polarized calculation instead?


IMHO, you should use the spin-polarized results. Though, this depends on 
what you are doing...


Best wishes
Lyudmila Dobysheva
--
Physics-Techn.Institute,
Udmurt Federal Research Center, Ural Br. of Rus.Ac.Sci.
426000 Izhevsk Kirov str. 132
Russia
---
Tel. +7 (34I2)43-24-59 (office), +7 (9I2)OI9-795O (home)
Skype: lyuka18 (office), lyuka17 (home)
E-mail: lyuk...@mail.ru (office), lyuk...@gmail.com (home)
___
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

[Wien] Spin-polarized DOS for dopants in non-magnetic materials

2019-01-18 Thread Marcelo Barbosa 
Dear all,

I’m calculating the DOS for dopants in semiconductors to get the corresponding 
impurity bands.
I’m dealing with non-magnetic materials and non-magnetic dopants, so I would 
assume that no spin-polarization was needed.
However, in some cases when substituting an atom for a dopant with different 
valence number, the DOS reveals an impurity band with different contributions 
from spin-up and spin-down due to the extra/missing electron. Also, the energy 
difference from the valence band maximum to the impurity band changes from a 
non spin-polarized calculation to a spin-polarized calculation.
My question then is: should I consider the spin-polarized results every time 
the spin-up and spin-down contributions are different? Or is there any good 
argument to choose the non spin-polarized calculation instead?

Regarding the impurity bands themselves, in the case of partially filled 
impurity bands, what is the correct energy value to report regarding the 
impurity band: the difference from the valence band maximum to the beginning of 
the entire impurity band or the difference from the valence band maximum to the 
minimum energy level of the unfilled region of the impurity band? 

Thank you for your help.

Best regards,
Marcelo
___
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