*** FILE AUTOMATICALLY CREATED: DO NOT EDIT, CHANGES WILL BE LOST ***
------------------------------------------------------------------------
INPUT FILE DESCRIPTION
Program: matdyn.x / PHonon / Quantum ESPRESSO (version: 6.6)
------------------------------------------------------------------------
Purpose of matdyn.x:
This program calculates the phonon frequencies for a list of generic
q vectors starting from the interatomic force constants generated
from the dynamical matrices as written by DFPT phonon code through
the companion program q2r.x
matdyn.x can generate a supercell of the original cell for mass
approximation calculation. If supercell data are not specified
in input, the unit cell, lattice vectors, atom types and positions
are read from the force constant file.
Input data format: [ ] = it depends
Structure of the input data:
========================================================================
&INPUT
...specs of the namelist variables...
/
[ X(1) Y(1) Z(1) ityp(1)
...
X(nat) Y(nat) Z(nat) ityp(nat) ]
[ nq
q_x(1) q_y(1) q_x(1) [ nptq(1) ]
...
q_x(nq) q_y(nq) q_x(nq) [ nptq(1) ] ]
========================================================================
NAMELIST: &INPUT
+--------------------------------------------------------------------
Variable: flfrc
Type: CHARACTER
Description: File produced by q2r containing force constants (needed)
It is the same as in the input of q2r.x (+ the .xml extension
if the dynamical matrices produced by ph.x were in xml
format). No default value: must be specified.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: asr
Type: CHARACTER
Default: 'no'
Description:
Indicates the type of Acoustic Sum Rule imposed.
Allowed values:
'no' :
no Acoustic Sum Rules imposed (default)
'simple' :
previous implementation of the asr used
(3 translational asr imposed by correction of
the diagonal elements of the force constants matrix)
'crystal' :
3 translational asr imposed by optimized
correction of the force constants (projection)
'one-dim' :
3 translational asr + 1 rotational asr imposed
by optimized correction of the dyn. mat. (the
rotation axis is the direction of periodicity; it
will work only if this axis considered is one of
the Cartesian axis).
'zero-dim' :
3 translational asr + 3 rotational asr imposed
by optimized correction of the dyn. mat.
Note that in certain cases, not all the rotational asr
can be applied (e.g. if there are only 2 atoms in a
molecule or if all the atoms are aligned, etc.).
In these cases the supplementary asr are cancelled
during the orthonormalization procedure (see below).
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: dos
Type: LOGICAL
Description: if .true. calculate phonon Density of States (DOS)
using tetrahedra and a uniform q-point grid (see below)
NB: may not work properly in noncubic materials
if .false. calculate phonon bands from the list of q-points
supplied in input (default)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variables: nk1, nk2, nk3
Type: INTEGER
Description: uniform q-point grid for DOS calculation (includes q=0)
(must be specified if @ref dos = .true., ignored otherwise)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: deltaE
Type: REAL
Description: energy step, in cm-1, for DOS calculation: from min
to max phonon energy (default: 1 cm-1 if ndos, see
below, is not specified)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: ndos
Type: INTEGER
Description: number of energy steps for DOS calculations
(default: calculated from deltaE if not specified)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: degauss
Type: REAL
Description: DOS broadening in cm-1
Default: 0 - meaning use tetrahedra
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: fldos
Type: CHARACTER
Description: output file for dos (default: 'matdyn.dos')
the dos is in states/cm-1 plotted vs omega in cm(-1)
and is normalised to 3*nat, i.e. the number of phonons
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: flfrq
Type: CHARACTER
Description: output file for frequencies (default: 'matdyn.freq')
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: flvec
Type: CHARACTER
Description: output file for normalized phonon displacements
(default: 'matdyn.modes'). The normalized phonon displacements
are the eigenvectors divided by the square root of the mass,
then normalized. As such they are not orthogonal.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: fleig
Type: CHARACTER
Description: output file for phonon eigenvectors (default: 'matdyn.eig')
The phonon eigenvectors are the eigenvectors of the dynamical
matrix. They are orthogonal.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: fldyn
Type: CHARACTER
Description: output file for dynamical matrix (default: ' ' i.e. not written)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: at(i,j), (i,j)=(1,1) ... (3,3)
Type: REAL
Description: supercell lattice vectors - must form a superlattice of the
original lattice (default: use original cell)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variables: l1, l2, l3
Type: INTEGER
Description: supercell lattice vectors are original cell vectors times
l1, l2, l3 respectively (default: 1, ignored if @ref at
specified)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: ntyp
Type: INTEGER
Description: number of atom types in the supercell
(default: "ntyp" of the original cell)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: amass(i), i=1,ntyp
Type: REAL
Description: masses of atoms in the supercell (a.m.u.), one per atom type
(default: use masses read from file flfrc)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: readtau
Type: LOGICAL
Description: read atomic positions of the supercell from input
(used to specify different masses) (default: .false.)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: fltau
Type: CHARACTER
Description: write atomic positions of the supercell to file fltau
(default: "fltau" = ' ', do not write)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: la2F
Type: LOGICAL
Description: if .true. interpolates also the el-ph coefficients
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: q_in_band_form
Type: LOGICAL
Description: if .true. the q points are given in band form:
only the first and last point of one or more lines
are given. See below. (default: .false.).
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: q_in_cryst_coord
Type: LOGICAL
Description: if .true. input q points are in crystalline
coordinates (default: .false.)
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: eigen_similarity
Type: LOGICAL
Description: use similarity of the displacements to order
frequencies (default: .false.)
NB: You cannot use this option with the symmetry
analysis of the modes.
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: fd
Type: LOGICAL
Description: if .true. the ifc come from the finite displacement calculation
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: na_ifc
Type: LOGICAL
Description: add non analitic contributions to the interatomic force
constants if finite displacement method is used (as in Wang et
al.
PRB 85, 224303 (2012)) [to be used in conjunction with fd.x]
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: nosym
Type: LOGICAL
Description: if .true., no symmetry and no time reversal are imposed
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: loto_2d
Type: LOGICAL
Description: set to .true. to activate two-dimensional treatment of LO-TO
splitting
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: loto_disable
Type: LOGICAL
Description: if .true. do not apply LO-TO splitting for q=0
(default: .false.)
+--------------------------------------------------------------------
===END OF NAMELIST======================================================
________________________________________________________________________
* IF readtau == .true. :
========================================================================
CARD:
IF ("READTAU") ATOMIC POSITIONS MUST BE SPECIFIED AS FOLLOWS:
/////////////////////////////////////////
// Syntax: //
/////////////////////////////////////////
X(1) Y(1) Z(1) ityp(1)
X(2) Y(2) Z(2) ityp(2)
. . .
X(nat) Y(nat) Z(nat) ityp(nat)
/////////////////////////////////////////
DESCRIPTION OF ITEMS:
+--------------------------------------------------------------------
Variables: X, Y, Z
Type: REAL
Description: X, Y, Z atomic positions
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: ityp
Type: INTEGER
Description: index of the atomic type
+--------------------------------------------------------------------
===END OF CARD==========================================================
ENDIF
________________________________________________________________________
________________________________________________________________________
* IF q_in_band_form == .true .and. dos == .false. :
========================================================================
CARD:
IF ("Q_IN_BAND_FORM" .AND. .NOT."DOS") Q-POINTS MUST BE SPECIFIED AS FOLLOWS:
/////////////////////////////////////////
// Syntax: //
/////////////////////////////////////////
nq
q_x(1) q_y(1) q_z(1) nptq(1)
q_x(2) q_y(2) q_z(2) nptq(2)
. . .
q_x(nq) q_y(nq) q_z(nq) nptq(nq)
/////////////////////////////////////////
DESCRIPTION OF ITEMS:
+--------------------------------------------------------------------
Variable: nq
Type: INTEGER
Description: number of q points
+--------------------------------------------------------------------
Description: The format of the q-points specification is:
(q(i,n),i=1,3), nptq
nptq is the number of points between this point
and the next. These points are automatically
generated. the q points are given in Cartesian
coordinates, 2pi/a units (a = lattice parameters)
+--------------------------------------------------------------------
Variables: q_x, q_y, q_z
Type: REAL
Description: coordinates of the Q point
+--------------------------------------------------------------------
+--------------------------------------------------------------------
Variable: nptq
Type: INTEGER
Description: The number of points between this point and the next.
"nptq" is the number of points between this point
and the next. These points are automatically
generated. the q points are given in Cartesian
coordinates, 2pi/a units (a = lattice parameters)
+--------------------------------------------------------------------
===END OF CARD==========================================================
* ELSE IF dos == .false. :
IF (.NOT. "DOS") Q-POINTS MUST BE SPECIFIED AS FOLLOWS:
========================================================================
CARD:
/////////////////////////////////////////
// Syntax: //
/////////////////////////////////////////
nq
q_x(1) q_y(1) q_z(1)
q_x(2) q_y(2) q_z(2)
. . .
q_x(nq) q_y(nq) q_z(nq)
/////////////////////////////////////////
DESCRIPTION OF ITEMS:
+--------------------------------------------------------------------
Variable: nq
Type: INTEGER
Description: number of q points
+--------------------------------------------------------------------
Description: The format of the q-points specification is:
((q(i,n),i=1,3), n=1,nq)
+--------------------------------------------------------------------
Variables: q_x, q_y, q_z
Type: REAL
Description: q-points in cartesian coordinates, 2pi/@i a units (@i a =
lattice parameters)
+--------------------------------------------------------------------
===END OF CARD==========================================================
ENDIF
________________________________________________________________________
:::: Notes
If q = 0, the direction qhat (q=>0) for the non-analytic part
is extracted from the sequence of q-points as follows:
qhat = q(n) - q(n-1) or qhat = q(n) - q(n+1)
depending on which one is available and nonzero.
For low-symmetry crystals, specify twice q = 0 in the list
if you want to have q = 0 results for two different directions
This file has been created by helpdoc utility on Mon Jul 19 14:16:03 CEST 2021
