Exact meaning of Strength from sort_and_report

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xtbu
Posts: 11
Joined: Sat Jul 20, 2019 4:15 am

Re: Exact meaning of Strength from sort_and_report

Post by xtbu » Fri May 22, 2020 5:27 pm

Dear all,
The dipoles extracted from ndb.dip_R with the unit of length (Bohr) or chargr*length?
And since the unit of residuals is energy, then the |BS_R|^2 should be energy*length. But why BS_R/q0_def_norm are in length unit as Palummo posted in the previous reply?

Thanks!

Xiangtian
Xiangtian Bu, M.S.
School of Physical Science and Technology, Inner Mongolia University, Hohhot, P. R. China

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Daniele Varsano
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Re: Exact meaning of Strength from sort_and_report

Post by Daniele Varsano » Sat May 23, 2020 9:42 am

Dear Xiangtan,

Here we use Hartree atomic units. The dipoles have charge*lenght units (e=1).
BS_R is defined as <c|e^iq.r|v> which for q=0 is then treated as q0.<c|r|v> where q0 is a small momentum (10^-5).
Thus BS_R/qo has length unit.

The dielectric permittivity in atomic units has e^2/(ao*Eh) units, or equivalently 4*pi*eps_0.

Best,
Daniele
Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/

xtbu
Posts: 11
Joined: Sat Jul 20, 2019 4:15 am

Re: Exact meaning of Strength from sort_and_report

Post by xtbu » Sat May 23, 2020 5:00 pm

Thanks, Daniele. I got the point!

Xiangtian
Xiangtian Bu, M.S.
School of Physical Science and Technology, Inner Mongolia University, Hohhot, P. R. China

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