Band gap of spin polarised ZGNR

[GJK]

Hi,

I have scrolled through the posts regarding Band Gap in the forum.
Thanks for the scripts for calculating the direct and indirect band gap.
It will be highly grateful if you could provide the scripts for calculating the,
1. overall band gap value(from spin up and spin down states)
2. Spin up band gap value
3.Spin down band gap value for the spin polarised ZGNR.

[Umberto Martinez]

Did you check this one?
bandstructure-analyzer.py in
http://quantumwise.com/documents/tutorials/latest/NanowireDevice/index.html/chap.nanowirebulk.html#sect2.nanowirebulk.analyze

It works also for a single Bandstructure object.
In the log window you will read the band gaps, and band edges for the Spin.Up and Spin.Down components.

[GJK]

Thank you Martinez,will revert to you after analysing the bandgap.

In the tutorials I have seen ZGNR with spin polarisation ---Is it Possible to calculate the overall band gap(spin up and spin down components) because the output of the .py file in the script provided by you gives spin up and spin down components only.

[GJK]

Did you check this one?
bandstructure-analyzer.py in
http://quantumwise.com/documents/tutorials/latest/NanowireDevice/index.html/chap.nanowirebulk.html#sect2.nanowirebulk.analyze

It works also for a single Bandstructure object.
In the log window you will read the band gaps, and band edges for the Spin.Up and Spin.Down components.

Hi Mr.Martinez,

I tried the script which u gave for custom builder.
But the Band gap values are shown as negative and the valence band and conduction band values are interchanged when I drag and drop my .nc file of ZGNR in to the custom builder.


Actually ZGNR should not have a bandgap(semi metal).But the output is showing different negative values for Band gap and Direct Bandgap .

No Bandgap means value should be zero know?because I have a band crossing at the Fermilevel clearly seen in the band structure.Kindly sort out this issue.I followed exactly the same procedure given for the silicon nanowire.But -ve results??

[Umberto Martinez]

maybe you can copy and paste the text printed in the log window. To compare with the bandstructure plot.

[Anders Blom]

If you know the band gap is zero from the plot, why bother computing it? A script designed to calculate the band gap will always assume there is one, and may fail if it's zero.

[GJK]

So nice of you Dr.Anders.
Really really thank you so much for the answer fruitfully.

[GJK]

Dear Dr.Anders I calculated the band gap using the available custom builder by seeing the band structure.

I used the custom builder to calculate spin polarised band structure of GNR. Though I  see a clear band gap with spin up and down components,to estimate the value when I use the builder it is showing one correct value and the other one wrong value.Ur assistance will be appreciable.