Input File Description

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

TABLE OF CONTENTS

INTRODUCTION

&PROJWFC

prefix | outdir | ngauss | degauss | Emin | Emax | DeltaE | lsym | pawproj | filpdos | filproj | lwrite_overlaps | lbinary_data | kresolveddos | tdosinboxes | n_proj_boxes | irmin(3,n_proj_boxes) | irmax(3,n_proj_boxes) | plotboxes

Notes

Format of output files
Orbital Order
Defining boxes for the Local DOS(E)
Important notices

INTRODUCTION

Purpose of projwfc.x:
    projects wavefunctions onto orthogonalized atomic wavefunctions,
    calculates Lowdin charges, spilling parameter, projected DOS
    (separated into up and down components for lSDA)
    alternatively, computes the local DOS(E), integrated in volumes
    given in input

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

   &PROJWFC
     ...
   /
   

Namelist: &PROJWFC

prefix CHARACTER
Default: 'pwscf'
prefix of input file produced by pw.x (wavefunctions are needed)
         
outdir CHARACTER
Default: value of the ESPRESSO_TMPDIR environment variable if set; current directory ('./') otherwise
directory containing the input data, i.e. the same as in pw.x
         
ngauss INTEGER
Default: 0
Type of gaussian broadening:
    0 ... Simple Gaussian (default)
    1 ... Methfessel-Paxton of order 1
   -1 ... Marzari-Vanderbilt "cold smearing"
  -99 ... Fermi-Dirac function
         
degauss REAL
Default: 0.0
 gaussian broadening, Ry (not eV!)
         
Emin, Emax REAL
Default: (band extrema)
 min & max energy (eV) for DOS plot
         
DeltaE REAL
 energy grid step (eV)
         
lsym LOGICAL
Default: .true.
if .true.  the projections are symmetrized,
           the partial density of states are computed
if .false. the projections are not symmetrized, the partial
           DOS can be computed only in the k-resolved case
         
pawproj LOGICAL
Default: .false.
if .true. use PAW projectors and all-electron PAW basis
functions to calculate weight factors for the partial
densities of states. Following Bloechl, PRB 50, 17953 (1994),
Eq. (4 & 6), the weight factors thus approximate the real
charge within the augmentation sphere of each atom.
Only for PAW, not implemented in the noncolinear case.
         
filpdos CHARACTER
Default: (value of prefix variable)
 prefix for output files containing PDOS(E)
         
filproj CHARACTER
Default: (standard output)
file containing the projections
         
lwrite_overlaps LOGICAL
Default: .false.
if .true., the overlap matrix of the atomic orbitals
prior to orthogonalization is written to the atomic_proj datafile.
         
lbinary_data LOGICAL
Default: .false.
if .true., the atomic_proj datafile is written in binary fmt.
         
kresolveddos LOGICAL
Default: .false.
if .true. the k-resolved DOS is computed: not summed over
all k-points but written as a function of the k-point index.
In this case all k-point weights are set to unity
         
tdosinboxes LOGICAL
Default: .false.
if .true. compute the local DOS integrated in volumes

Volumes are defined as boxes with edges parallel to the unit cell,
containing the points of the (charge density) FFT grid included within
irmin and irmax, in the three dimensions:

from irmin(j,n) to irmax(j,n) for j=1,2,3 (n=1,n_proj_boxes).
         
n_proj_boxes INTEGER
Default: 1
number of boxes where the local DOS is computed
         
irmin(3,n_proj_boxes) INTEGER
Default: 1 for each box
first point of the given box

BEWARE: irmin is a 2D array of the form: irmin(3,n_proj_boxes)
         
irmax(3,n_proj_boxes) INTEGER
Default: 0 for each box
last point of the given box;
( 0 stands for the last point in the FFT grid )

BEWARE: irmax is a 2D array of the form: irmax(3,n_proj_boxes)
         
plotboxes LOGICAL
Default: .false.
if .true., the boxes are written in output as xsf files with
3D datagrids, valued 1.0 inside the box volume and 0 outside
(visualize them as isosurfaces with isovalue 0.5)
         

Notes

Format of output files

Projections are written to standard output, and also to file
filproj if given as input.

The total DOS and the sum of projected DOS are written to file
"filpdos".pdos_tot.

* The format for the collinear, spin-unpolarized case and the
  non-collinear, spin-orbit case is:
      E DOS(E) PDOS(E)
      ...

* The format for the collinear, spin-polarized case is:
      E DOSup(E) DOSdw(E)  PDOSup(E) PDOSdw(E)
      ...

* The format for the non-collinear, non spin-orbit case is:
      E DOS(E) PDOSup(E) PDOSdw(E)
      ...

In the collinear case and the non-collinear, non spin-orbit case
projected DOS are written to file "filpdos".pdos_atm#N(X)_wfc#M(l),
where N = atom number , X = atom symbol, M = wfc number, l=s,p,d,f
(one file per atomic wavefunction found in the pseudopotential file)

* The format for the collinear, spin-unpolarized case is:
      E LDOS(E) PDOS_1(E) ... PDOS_2l+1(E)
      ...
  where LDOS = \sum m=1,2l+1 PDOS_m(E)
  and PDOS_m(E) = projected DOS on atomic wfc with component m

* The format for the collinear, spin-polarized case and the
  non-collinear, non spin-orbit case is as above with
  two components for both  LDOS(E) and PDOS_m(E)

In the non-collinear, spin-orbit case (i.e. if there is at least one
fully relativistic pseudopotential) wavefunctions are projected
onto eigenstates of the total angular-momentum.
Projected DOS are written to file "filpdos".pdos_atm#N(X)_wfc#M(l_j),
where N = atom number , X = atom symbol, M = wfc number, l=s,p,d,f
and j is the value of the total angular momentum.
In this case the format is:
    E LDOS(E) PDOS_1(E) ... PDOS_2j+1(E)
    ...

If kresolveddos=.true., the k-point index is prepended
to the formats above, e.g. (collinear, spin-unpolarized case)
    ik E DOS(E) PDOS(E)

All DOS(E) are in states/eV plotted vs E in eV
         

Orbital Order

Order of m-components for each l in the output:

    1, cos(phi), sin(phi), cos(2*phi), sin(2*phi), .., cos(l*phi), sin(l*phi)

where phi is the polar angle:x=r cos(theta)cos(phi), y=r cos(theta)sin(phi)
This is determined in file Modules/ylmr2.f90 that calculates spherical harmonics.

for l=1:
  1 pz     (m=0)
  2 px     (real combination of m=+/-1 with cosine)
  3 py     (real combination of m=+/-1 with sine)

for l=2:
  1 dz2    (m=0)
  2 dzx    (real combination of m=+/-1 with cosine)
  3 dzy    (real combination of m=+/-1 with sine)
  4 dx2-y2 (real combination of m=+/-2 with cosine)
  5 dxy    (real combination of m=+/-2 with sine)
         

Defining boxes for the Local DOS(E)

Boxes are specified using the variables irmin and irmax:

FFT grid points are included from irmin(j,n) to irmax(j,n)
for j=1,2,3 and n=1,...,n_proj_boxes

irmin and irmax range from 1 to nr1 or nr2 or nr3

Values larger than nr1/2/3 or smaller than 1 are folded
to the unit cell.

If irmax<irmin FFT grid points are included from 1 to irmax
and from irmin to nr1/2/3.
         

Important notices

* The tetrahedron method is presently not implemented.

* Gaussian broadening is used in all cases:

    - if degauss is set to some value in namelist &PROJWFC, that value
      (and the optional value for ngauss) is used

    - if degauss is NOT set to any value in namelist &PROJWFC, the
      value of degauss and of ngauss are read from the input data
      file (they will be the same used in the pw.x calculations)

    - if degauss is NOT set to any value in namelist &PROJWFC, AND
      there is no value of degauss and of ngauss in the input data
      file, degauss=DeltaE (in Ry) and ngauss=0 will be used


Obsolete variables, ignored:
    io_choice
    smoothing
         
This file has been created by helpdoc utility on Mon Oct 23 19:37:12 CEST 2017.