Structure of the input data:
===============================================================================
&inputgw
...
/
Frequencies
...
/
K_points
...
/
========================================================================
NAMELIST: &inputgw
+--------------------------------------------------------------------
Variable: do_coulomb, do_green, do_sigma_exx, do_sigma_c,
do_sigma_matel.
Type: LOGICAL
Default: .false.
Description: control variables for determining which aspects of
the calculation are to be run. In order: perform calculation
of screened coulomb interaction, the Green's function, exact
exchange component of the interaction, the correlation
energy, and the matrix elements of the single particle
states with the various operators.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: prefix
Type: CHARACTER
Default: 'sgw'
Description: prepended to input/output filenames:
prefix.wfc, prefix.rho, etc. Must be the same
as the underlying scf calculation.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: use_symm
Type: LOGICAL
Default: .TRUE.
Description: Logical variable to determine whether or not symmetry
is used to reduced the number of independent solutions
of the Sternheimer equation required. use_symm only
calculates electronic response to unique G vectors.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: do_imag
Type: LOGICAL
Default: .false.
Description: Performs calculation along imaginary axis. Both the
Green's function and the screened Coulomb interaction
are calculated along the imaginary, the convolution
is performed using a Gauss-Legendre grid. Significant
saving in time and memory compared to real frequency
integration.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: ecutsco, ecutsex
Type: REAL(DP)
Default: 5 Ry.
Description: Planewave energy cutoffs for the (co)rrelation energy and
the (ex)change energy. Typically a higher cutoff for the
exchange energy is required.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: godbyneeds, padecont, freq_gl
Type: LOGICAL
Default: godbyneeds
Description: Choice of screening model for the screened Coulomb
interaction. The Godby-Needs plasmon pole model
requires fitting the dielectric function to two points
on the imaginary axis, typically at 0, and i\omega_{p}
where \omega_{p} is the classical plasmon frequency.
The padecont chooses analytic continuation of the frequency
dependence. freq_gl only calculates the screened Coulomb
interaction at the points required by the Gauss-Legendre grid.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: maxter_green
Type: INTEGER
Default: 200
Description: Maximum number of conjugate gradient minimization steps.
A warning will be issued if the linear system does not
converge for multishift. In this case you may have to
raise maxter_green or abandon the multishift linear system
solver.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: nbnd_sig
Type: INTEGER
Default: number of occupied bands + 4
Description: Number of bands included in the final ouput. Typically
one is interested in the selfenergy, quasiparticle corrections,
and self-energy operator for the states around the band
gap or Fermi energy.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable:
Type:
Default:
Description:
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable:
Type:
Default:
Description:
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: wcoulmax
Type: REAL
Default: 80 eV
Description: The cutoff in eV of the frequency dependence of the Screened
Coulomb interaction.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: wsigmamin, wsigmamax, deltaw
Type: REAL
Default: 0.0 eV, 20.0 eV, 5.0 eV
Description: The minimum and maximum, and spacing, of the frequency points
for the selfenergy. In the case of do_imag, these are the
frequency points along the imaginary axis which are fitted
to perform the analytic continuation. For real frequencies
a much finer grid would be required.
+--------------------------------------------------------------------
FREQUENCIES
Line of input:
nfs
w(1) w(2)
....
w(1) w(2)
DESCRIPTION OF ITEMS:
+--------------------------------------------------------------------
Variable : nfs
Type: INTEGER
Description: Number of frequency points in the calculation of W(iw).
If the Godby-Needs plasmon-pole model is used only two
frequency points are required. For the analytic
continuation more points are required
+--------------------------------------------------------------------
K_Points
========================================================================
Line of input:
nqs
xq(1) xq(2) xq(3)
DESCRIPTION OF ITEMS:
+--------------------------------------------------------------------
Variable : nqs
Type: INTEGER
Description: number of q points
Variables: xq(1) xq(2) xq(3)
Type: REAL
Description: The electric field wavevectors, or the point at which
Sigma_{q} is calculated in units of 2pi/a0
(a0 = lattice parameter).
+--------------------------------------------------------------------
===End of line-of-input=================================================