Correct way to force oxidation state?

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cameronu
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Correct way to force oxidation state?

#1 Post by cameronu » Fri Aug 16, 2019 3:24 pm

Hi,

I am wishing to force the oxidation state of Sn in MASnI3 to be 4+ rather than the equilibrium 2+.

I have set NELECT = 48 rather than the expected 50 and explicitly set the Sn 5p occupancy to 0 in the POTCAR.

Is this reasonable or should I be setting the MAGMOM tag too?

Thanks in advance,

Cameron

cameronu
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Re: Correct way to force oxidation state?

#2 Post by cameronu » Wed Aug 21, 2019 4:41 pm

I have tested the charge per atom using bader charge analysis and noted that the charge for Sn has dropped from 13.146978 in the case of 2+ to 12.882354 in the case of 4+, so I am concerned this method did not work. If anybody knows of a good way to force the two electrons to be 'removed' from Sn please let me know.

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Re: Correct way to force oxidation state?

#3 Post by admin » Thu Nov 07, 2019 8:28 am

The oxidation state of an atom is defined by surrounding atoms
and bonding to them. The change of the oxidation state can be achieved
with the change of the composition of the surrounding atomic sphere.
The variation of NELECT changes the number of electrons in the system
and does not lead to the local change on a specific atom.

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