Input File Description

Program: turbo_eels.x / turboEELS / Quantum ESPRESSO (version: 6.7GPU)

TABLE OF CONTENTS

INTRODUCTION

&LR_INPUT

prefix | outdir | restart | restart_step | lr_verbosity | disk_io

&LR_CONTROL

approximation | q1 | q2 | q3 | calculator | itermax | pseudo_hermitian | alpha_mix(i) | epsil | units | start | end | increment | ethr_nscf

INTRODUCTION

    Input data format: { } = optional, [ ] = it depends.

All quantities whose dimensions are not explicitly specified are in
RYDBERG ATOMIC UNITS

BEWARE: TABS, DOS <CR><LF> CHARACTERS ARE POTENTIAL SOURCES OF TROUBLE

Comment lines in namelists can be introduced by a "!", exactly as in
fortran code. Comments lines in ``cards'' can be introduced by
either a "!" or a "#" character in the first position of a line.

Structure of the input data:
===============================================================================

&LR_INPUT
  ...
/

&LR_CONTROL
  ...
/
   

Namelist: &LR_INPUT

This namelist is always needed !

prefix CHARACTER
Default: 'pwscf'
Sets the prefix for generated and read files. The files
generated by the ground state pw.x run must have this
same prefix.
         
outdir CHARACTER
Default: './'
The directory that contains the run critical files, which
include the files generated by ground state pw.x run.
         
restart LOGICAL
Default: .false.
When set to .true., turbo_eels.x will attempt to restart
from a previous interrupted calculation. (see restart_step
variable).
Beware, if set to .false. turbo_eels.x will OVERWRITE any
previous runs.
         
restart_step INTEGER
Default: itermax
The code writes restart files every restart_step iterations.
Restart files are automatically written at the end of
itermax Lanczos steps.
         
lr_verbosity INTEGER
Default: 1
This integer variable controls the amount of information
written to standard output.
         
disk_io CHARACTER
Default: 'default'
    Fine control of disk usage. Currently only 'reduced' is
supported where no restart files are written, apart from
the 'default' mode.
         

Namelist: &LR_CONTROL

approximation CHARACTER
Default: 'TDDFT'
 A string describing a level of theory:
            
'TDDFT' :
Time-Dependent Local Density Approximation or
Time-Dependent Generalized Gradient Approximation
(depending on the XC functional)
            
'IPA' :
Independent Particle Approximation (IPA)
            
'RPA_with_CLFE' :
Random Phase Approximation (RPA) with
Crystal Local Field Effects (CLFE)
            
q1, q2, q3 REAL
Default: 1.0, 1.0, 1.0
The values of the transferred momentum q = (q1, q2, q3)
in Cartesian coordinates in units of 2pi/a, where
"a" is the lattice parameter.
         
calculator CHARACTER
Default: 'lanczos'
Variable that controls which algorithm is used to compute EELS spectra.
            
'lanczos' :
corresponds to the Lanczos recursive algorithm
            
'sternheimer' :
corresponds to the Sternheimer algorithm
            
itermax INTEGER
Default: 500
When calculator = 'lanczos', itermax is the
maximum number of Lanczos iterations that will be performed.
When calculator = 'sternheimer', itermax is the
maximum number of iterations in a SCF step for each frequency.
         
pseudo_hermitian LOGICAL
Default: .true.
This variable is used only when calculator = 'lanczos'.
When set to .true. the pseudo-Hermitian Lanczos algorithm is
used. When set to .false. the non-Hermitian Lanczos
biorthogonalization algorithm is used (which is two times slower).
         
alpha_mix(i) REAL
Default: alpha_mix(1)=0.7
This variable is used only when calculator = 'sternheimer'.
Mixing parameter (for the i-th iteration) for updating
the response SCF potential using the modified Broyden
method: D.D. Johnson, PRB 38, 12807 (1988).
         
epsil REAL
Default: 0.02
This variable is used only when calculator = 'sternheimer'.
The broadening/damping term (in Rydberg units).
         
units INTEGER
Default: 0
This variable is used only when calculator = 'sternheimer'.
The unit system used for the output, for start, end,
and increment input parameters.
0 = Rydbergs, 1 = Electron volts.
         
start REAL
Default: 0.0
See: end, increment
This variable is used only when calculator = 'sternheimer'.
start is the value of frequency starting from which the
susceptibility and the loss function (-Im(1/eps)) will be computed.
start is specified in units controlled by units.
         
end REAL
Default: 2.5
See: start, increment
This variable is used only when calculator = 'sternheimer'.
end is the value of frequency up to which the
susceptibility and the loss function (-Im(1/eps)) will be computed.
end is specified in units controlled by units.
         
increment REAL
Default: 0.001
See: start, end
This variable is used only when calculator = 'sternheimer'.
increment is an incremental step used to define the mesh
of frequencies between start and end.
increment is specified in units controlled by units.
         
ethr_nscf REAL
Default: 1.D-11
Threshold for the convergence of eigenvalues during
the iterative diagonalization of the Hamiltonian in
the non-self-consistent-field (NSCF) calculation at
k and k+q points. Note, this quantity is NOT extensive.
         
This file has been created by helpdoc utility on Fri Apr 23 19:45:01 CEST 2021.