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E-RIM

Posted: Wed May 14, 2014 10:39 am
by martinspenke
Dear Daniele,

At point 7 of http://www.yambo-code.org/input_file/ypp/ypp_rim.php
how can i include the ndb.E_RIM data base in GW and BSE yambo.input to restart the calculation.
What is here the keyword for this ?

Bests
Martin

Re: E-RIM

Posted: Wed May 14, 2014 11:19 pm
by Davide Sangalli
Dear Martin,
once the ndb.E_RIM will be inside the SAVE folder yambo will use it whenever it can.

In particular in BSE it will be used if you use the inversion solver: BSSmod= "i"
In GW calculation I think it is used if you go beyond the plasmon pole approximation in the computation of the inverse dielectric matrinx on the real axis.
Finally in the computation of the dielectric function in the reciprocal space (yambo -o c ) it should be alway used

Best,
Davide

Re: E-RIM

Posted: Thu May 15, 2014 12:18 am
by Daniele Varsano
BSSmod="i"
I think.

Daniele

Re: E-RIM

Posted: Thu May 15, 2014 11:49 am
by martinspenke
A further question :

which method is used in yambo to calculate the inverse of microscopic dielectric function on the fine grid controlled by ETStpsXd ?
Is it contour deformation technique which is also applied in abinit ?

Bests
Martin

Re: E-RIM

Posted: Thu May 15, 2014 1:39 pm
by Daniele Varsano
Dear Martin,
it is not the deformation contour technique, but a real axis integration as explained in the Yambo paper, equation 5.
Best,
Daniele

Re: E-RIM

Posted: Thu May 15, 2014 1:53 pm
by martinspenke
Dear Daniele,

okay, i see ths in paper, but how is then the frequency integral of the correlation part of self energy is calculated in yambo if no deformation technique is applied?

Bests
Martin

Re: E-RIM

Posted: Thu May 15, 2014 2:01 pm
by Daniele Varsano
Dear Martin,
it is a real axis integration, so you have to choose the spacing of your frequencies (ie the number of frequency in a given interval) and converge with respect this parameter. It is usually a very cumbersome calculation.
YOu can have a look to this tutorial:
http://www.yambo-code.org/tutorials/Rea ... /index.php

Best,
Daniele

Re: E-RIM

Posted: Thu May 15, 2014 2:11 pm
by martinspenke
Dear Daniele,

i know this, i was just comparing it with abinit calculation method for the correlation part of self energy which is deformation technique.
Here http://www.abinit.org/documentation/hel ... y_mbt.html they say :

Code: Select all

The contour deformation method was proposed in order to avoid having to deal with quantities close to the real axis as much as possible.
I was just wondering that in yambo for frequency integral calculations in dielectric function and correlation part of self energy one uses real axis frequency method and not hilbert transform and deformation technique methods
Any way sorry and thank you.

Bests
Martin