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.
|
|
|
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