ngeo(1),...,ngeo(6) : the number of geometries to use for each
celldm parameter. The lattice constant of these
geometries is calculated from the input of pw.x.
celldm(1),...,celldm(6) of this input is used
for the central geometry. For the others celldm(1),
...,celldm(6), are changed in steps of step_ngeo(1),
...,step_ngeo(6). ngeo(1) must be odd. Only the
values of celldm relevant for each Bravais lattice
are actually changed.
Default: integer 1,1,1,1,1,1 for what=scf_*,
9,1,1,1,1,1 for what=mur_lc_* and lmurn=.TRUE. or
for cubic systems, 5 on all the relevant celldm
parameters when lmurn=.FALSE. and the system
is not cubic.
step_ngeo(1),...,step_ngeo(6) : The step between the lattice
constants at different geometries. step_ngeo(1) is,
in atomic units, the change of a, step_ngeo(2),
step_ngeo(3) are dimensionless and are the changes
of the ratios b/a, c/a, step_ngeo(4), step_ngeo(5),
step_ngeo(6) are the changes in degree of the
angles alpha, beta, and gamma. The cosine of the
angle is calculated by the program.
Default: real 0.05 a.u., 0.02, 0.02, 0.5, 0.5, 0.5
lmurn : if .TRUE. the fit with an equation of state
is done. Only ngeo(1) values of the energy are
fitted, the other values
of ngeo are not used. if .FALSE. use a quadratic
or quartic function to interpolate the energy as
a function of all celldm parameters. The number of
self-consistent calculations is ngeo(1) x ngeo(2)
x ngeo(3) x ngeo(4) x ngeo(5) x ngeo(6). In this
case only the minimum energy and the optimal celldm
are given in output.
Default: .TRUE.
ieos : choose the equation of state to use (only when
lmurn=.TRUE.):
1 - Birch-Murnaghan third order
2 - Birch-Murnaghan fourth order
4 - Murnaghan
Default: integer 4
show_fit : if .TRUE. show the contour plot of the fitted
energy instead of the energy. Used by default
when reduced_grid is .TRUE..
Default: logical .FALSE.
frozen_ions: if .TRUE. the atomic coordinates are obtained by
applying the strain to the coordinates given in the
pw.x input to the new cell parameters (equivalent to
keep the crystal coordinates fixed) and kept fixed.
If .FALSE. the atomic coordinates are relaxed at
each geometry.
Default: logical .FALSE.
vmin_input : minimum volume for the plot of the energy as a
function of volume.
Default: real 0.98 times the volume of the first
geometry.
vmax_input : maximum volume for the plot of the energy as a
function of volume.
Default: real 1.02 times the volume of the last
geometry.
deltav : distance between two volumes in the plot of the
energy as a function of the volume.
Default: real calculated from nvol.
nvol : number of volumes in equation of state plot.
Default: integer 51
lquartic : if .TRUE. fit the energy with a quartic polynomial.
Default: logical .TRUE.
lsolve : choose the algorithm used to fit the quartic
polynomial parameters.
Allowed values:
1 explicitly minimize chi^2 (usually less accurate
than the other two. Should be used only for tests).
2 Use the QR algorithm to minimize chi^2 (lapack
routine dgels) 3 Use the SVD algorithm to minimize
chi^2 (lapack routine dgelss).
Default: integer 2
flevdat : file where the equation of state is written. The
results of the fit are then written in
flevdat.ev.out.
Default: character(len=*) 'output_ev.dat'
flpsmur : postscript file of the equation of state plot.
Default: character(len=*) 'output_mur'
lel_free_energy : if .TRUE. computes the electronic thermodynamic
properties (energy, free energy, entropy, and constant
strain heat capacity) at each temperature and plots
them. See the scf_dos option for the parameters that
control the calculation.
Default: .FALSE.
ncontours : the number of contours in the energy plot. These
levels can be determined automatically by the code
or defined by the user. The energy levels can be
defined after the INPUT_THERMO namelist but before
the path, as a list:
energy_level(1) color(1)
...
energy_level(ncontours) color(ncontours)
Color is a string of the type color_red, color_green,
etc.
The list of available colors is at the beginning of
each gnuplot script. energy_level is in Ry units.
Default: integer 9
do_scf_relax : if .TRUE. the code makes a self-consistent relax
calculation at the equilibrium geometry to find
the optimized atomic coordinates. This step is
needed only for solids that have internal degrees
of freedom in the unstrained configuration.
If .FALSE. the coordinates of the input geometry
are strained uniformly to the equilibrium geometry.
Default: logical .FALSE.
lgeo_from_file : if .TRUE. the input geometries are read from file.
ngeo(1) must have the total number of geometries
and lmurn must be .TRUE..
Default : .FALSE.
lgeo_to_file : if .TRUE. at the end of the calculation the code
writes in a file the geometries that correspond to
the optimized crystal parameters for each value of
celldm(1) of the grid of geometries.
Default : .FALSE.
flenergy : name of the file that contains the energy in a
form that can be used by gnuplot to make contour
plots.
Default: character(len=*) 'output_energy'
flgeom : name of the file that contains the geometries
requested with the flags lgeo_to_file or
lgeo_from_file. The file is in the directory
energy files.
Default: character(len=*) 'output_geometry'
flpsenergy : file with the contour plots of the energy as a
function of the crystal parameters.
Default: character(len=*) 'output_energy'
An example for this option can be found in example05.
Number of tasks for this option:
ngeo(1) when lmurn=.TRUE.,
ngeo(1)
x