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The Unit for isovalue in cut3d

Posted: Mon Dec 24, 2012 10:58 am
by wangyongphysik
Dear all,

I did some ground state calculations with ABINIT code, and then used "cut3d" to generate the "xsf" file to plot the isosurface of the charge density distribution . However, I am not sure what is the unit used here for the isovalue. Is it "e/A^{3}" or "e/"Bohr^{3}" or something else ?
I am looking forward to your replies.
All the Best,
Yong Wang

Re: The Unit for isovalue in cut3d

Posted: Tue May 15, 2018 11:07 pm
by ckunka
Did you ever find an answer? I too would like to know the units of the electronic density in the .xsf file.

From the below page, the density output files (_DEN) seem to be in electrons/Bohr^3. I'm just not sure if I should assume this unit is maintained in .xsf.

https://www.abinit.org/sites/default/fi ... outputfile

I didn't see any mention of units here:
https://www.abinit.org/sites/default/fi ... _help.html
https://www.abinit.org/sites/default/fi ... tools.html

Re: The Unit for isovalue in cut3d

Posted: Wed May 16, 2018 12:11 am
by gmatteo
From the below page, the density output files (_DEN) seem to be in electrons/Bohr^3. I'm just not sure if I should assume this unit is maintained in .xsf.


Yes, the density is in electrons/Bohr^3 (the same units used internally in the code).

Note that the lattice vectors and the atomic positions in the header of the XSF file are in Angstrom
(the XSF format specifies Angstrom units for the structural parameters but there's no metadata for the dimension of the scalar field)

Re: The Unit for isovalue in cut3d  [SOLVED]

Posted: Wed May 16, 2018 5:52 pm
by ckunka
Thanks!

It's strange that both Bohr and Angstrom are used in the same file...

Re: The Unit for isovalue in cut3d

Posted: Mon Oct 21, 2019 11:34 pm
by Hola
Hi everyone,

gmatteo wrote:Yes, the density is in electrons/Bohr^3 (the same units used internally in the code).

We we refer to "electrons", do we refer to the number of electrons or to the amount
of electronic charge in coulomb ? What is the unit of "electrons" ?

Best regards.