Yambo Community Forum

Dear all

I am reading the source code of yambo 4.0.1 and the file X_os.F in src/pol_funcion/ seems to calculate the \Chi_0.

In the file X_os.F, there are the following codes:
-------------------------------------------------------------------------------------------
loop_bare_grid: do i_bg = 1,bare_grid_N(i_cg)
!
n_poles=n_poles+1
!
! Scattering geometry
!---------------------
!
ikbz = X_poles_tab(n_poles,1)
iv = X_poles_tab(n_poles,2)
ic = X_poles_tab(n_poles,3)
i_spin = X_poles_tab(n_poles,4)
--------------------------------------------------------------------------------------------

My question is that whether the two variables (iv and ic) correspond to the band index in the summation in the computation of \Chi_0.
And the occupation for iv/ic is full/empty.

Could anyone please help me on this?

Dear Wei-Dong Cao,
If presume you mean X_os_residuals.F.
Yes, as you argued iv is the index of the valence bands hence occupied and ic indicate the conduction bands.
They are used for the computation of Xo.

Best,

Daniele

Dear Daniele Varsano

Thank you for your quick response.
Yes, I means the file X_os_residuals.F in the latest version of yambo (4.0.2 rev.90) and it really helps me a lot.

Best Wishes.