## Question concerning oscillator strentgh

Run-time issues concerning Yambo that are not covered in the above forums.

Moderators: Daniele Varsano, andrea marini, myrta gruning, Conor Hogan

martinspenke
Posts: 149
Joined: Tue Apr 08, 2014 6:05 am

### Question concerning oscillator strentgh

Dear Daniele,

if i want to calculate y-component of oscillator strength i have in my 06_BSE this keyword :

Code: Select all

% BLongDir
0.000000 | 1.000000 | 0.000000 |        # [BSS] [cc] Electric Field
%
but i also have this keyword in the input files of 03_real_axis and 05_W, too.
Now should i also have the same 0 1 0 in 03_real_axis and 05_W input files, too
or can i say, i let BLongDir in 03_real_axis and 05_W be 1 0 0 and calculate BSE in my 06_BSE with 0 1 0 configuration ???

Bests
Martin
Martin Spenke, PhD Student
Theoretisch-Physikalisches Institut
Universität Hamburg, Germany

Daniele Varsano
Posts: 2319
Joined: Tue Mar 17, 2009 2:23 pm
Contact:

### Re: Question concerning oscillator strentgh

Dear martin
The q limit in the absorption is determined in the bse part. You do not need to change the q limit in the screening and gw which affect the dielectric matrix which usually does not play an important role unless you have an highly anysotropic system.
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/

martinspenke
Posts: 149
Joined: Tue Apr 08, 2014 6:05 am

### Re: Question concerning oscillator strentgh

Dear Daniele,

What is the unit of the oscillator strength in yambo?

Bests
Martin
Martin Spenke, PhD Student
Theoretisch-Physikalisches Institut
Universität Hamburg, Germany

Daniele Varsano
Posts: 2319
Joined: Tue Mar 17, 2009 2:23 pm
Contact:

### Re: Question concerning oscillator strentgh

Dear Martin,
I think that the units are arbitrary. The absorption it is calculated as Im(\epsilon_m).

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/