Input File Description

Program: dynmat.x / PWscf / Quantum Espresso (version: 6.2)

TABLE OF CONTENTS

INTRODUCTION

&INPUT

fildyn | q | amass | asr | axis | lperm | lplasma | filout | fileig | filmol | filxsf

INTRODUCTION

Purpose of dynmat.x:

- reads a dynamical matrix file produced by the phonon code

- adds the non-analytical part (if Z* and epsilon are read from
  file), applies the chosen Acoustic Sum Rule (if q=0)

- diagonalise the dynamical matrix

- calculates IR and Raman cross sections (if Z* and Raman
  tensors are read from file, respectively)

- writes the results to files, both for inspection and for
  plotting


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

&INPUT
   ...specs of namelist variables...
/
   

Namelist: &INPUT

fildyn CHARACTER
Default: 'matdyn'
input file containing the dynamical matrix
         
q(i), i=1,3 REAL
Default: q = (0,0,0)
calculate LO modes (add non-analytic terms) along the direction q (Cartesian axis)
         
amass(i), i=1,ntyp REAL
Default: amass is read from file fildyn
mass for each atom type
         
asr CHARACTER
Default: 'no'
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 dynamical matrix)
            
'crystal' :
3 translational asr imposed by optimized
correction of the dyn. matrix (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 canceled during
the orthonormalization procedure (see below).

Finally, in all cases except 'no' a simple correction
on the effective charges is performed (same as in the
previous implementation).
            
axis INTEGER
Default: 3
indicates the rotation axis for a 1D system (1=Ox, 2=Oy, 3=Oz)
         
lperm LOGICAL
Default: .false.
if .true. then calculate Gamma-point mode contributions to
dielectric permittivity tensor
         
lplasma LOGICAL
Default: .false.
if .true. then calculate Gamma-point mode effective plasma
frequencies, automatically triggers lperm = .true.
         
filout CHARACTER
Default: 'dynmat.out'
output file containing phonon frequencies and normalized
phonon displacements (i.e. eigenvectors divided by the
square root of the mass and then normalized; they are
not orthogonal)
         
fileig CHARACTER
Default: ' '
output file containing phonon frequencies and eigenvectors
of the dynamical matrix (they are orthogonal)
         
filmol CHARACTER
Default: 'dynmat.mold'
as above, in a format suitable for molden
         
filxsf CHARACTER
Default: 'dynmat.axsf'
as above, in axsf format suitable for xcrysden
         
This file has been created by helpdoc utility on Mon Oct 23 19:37:10 CEST 2017.