What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

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What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#1 Post by hszhao.cn@gmail.com » Wed Jun 26, 2024 1:04 pm

Hi there,

What are the fractional superscripts used on the vasp wiki to indicate the Valence electron configuration?

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Zhao

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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#2 Post by hszhao.cn@gmail.com » Wed Jun 26, 2024 1:20 pm

See here for the related discussion.

pedro_melo
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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#3 Post by pedro_melo » Wed Jun 26, 2024 1:21 pm

Dear Zhao,

If you are referring to the "_h", "_sv", etc, there is a full explanation here wiki/index.php/Choosing_pseudopotentials, about which pseudopotential to choose depending on the type of calculation and system you want to study.

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Pedro

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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#4 Post by hszhao.cn@gmail.com » Wed Jun 26, 2024 2:04 pm

Dear Pedro,
pedro_melo wrote: Wed Jun 26, 2024 1:21 pm If you are referring to the "_h", "_sv", etc, there is a full explanation here wiki/index.php/Choosing_pseudopotentials, about which pseudopotential to choose depending on the type of calculation and system you want to study.
No. I mean something like the 1.99 and 0.01, as shown below, which is used for the Valence electron configuration:

Code: Select all

2s ^ {1.99}  2p ^ {0.01}
Regards,
Zhao

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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#5 Post by pedro_melo » Fri Jun 28, 2024 3:08 pm

Dear Zhao,

Those are the atomic reference configuration used when generating the pseudopotential. Fractional occupancies are sometimes used to improve results and facilitate transferability.

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Pedro

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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#6 Post by hszhao.cn@gmail.com » Sat Jun 29, 2024 1:05 am

See here for the related discussion.

Regards,
Zhao

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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#7 Post by pedro_melo » Mon Jul 01, 2024 10:20 am

Dear Zhao,

My apologies, I do not understand what you want me to see from the discussion thread you posted. The information about the fractional occupancies can be obtained from the POTCAR files in the " Atomic configuration" section of the file. Is there another question or something else I can help you with?

Kind regards,
Pedro

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Re: What do the fractional superscripts mean used on the vasp wiki for indicating the Valence electron configuration?

#8 Post by hszhao.cn@gmail.com » Mon Jul 01, 2024 11:44 am

Dear Pedro,

My confusion lies in the fact that this fractional occupation form is not reflected in the corresponding basis sets used by lobster. Fortunately, J. George has already explained my confusion.

Regards,
Zhao

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