[Pw_forum] Format of dynamical matrices

[Cristian Degli Esposti Boschi]

Dear all,

I have a couple of questions regarding the format of dynamical
matrices generated by ph.x.

(1) After the line "Dynamical Matrix in cartesian axes"
and the q-value (0 0 0 in my cases) I see a block
of 3 rows and 6 columns for each possible choice of say (n,m)
where n and m label the atoms. What do the entries of
the rows and columns represent? It seems that the second
element of every entry is always 0...

(2) After the line "Diagonalizing the dynamical matrix" and
the q-value, enclosed in two lines of ***** I see the dynamical
matrix expressed as eigenvalues/eigenvectors.
Are the components of the latter expressed (for every atom) in real 
space? Again what are the zeroes after each component?

I attach the output for fcc Si from example02.

Thanks for your time, Cristian

Dynamical matrix file

   1    2  2 10.2000000  0.0000000  0.0000000  0.0000000  0.0000000 
0.0000000
  1  'Si  '  25593.354256961386
     1    1      0.0000000      0.0000000      0.0000000
     2    1      0.2500000      0.2500000      0.2500000

      Dynamical  Matrix in cartesian axes

      q = (    0.000000000   0.000000000   0.000000000 )

   1  1
   0.27657353  0.00000000   -0.00000000  0.00000000    0.00000000 
0.00000000
   0.00000000  0.00000000    0.27657353  0.00000000    0.00000000 
0.00000000
   0.00000000  0.00000000    0.00000000  0.00000000    0.27657353 
0.00000000
   1  2
  -0.27655447  0.00000000   -0.00000000  0.00000000   -0.00000000 
0.00000000
  -0.00000000  0.00000000   -0.27655447  0.00000000    0.00000000 
0.00000000
  -0.00000000  0.00000000    0.00000000  0.00000000   -0.27655447 
0.00000000
   2  1
  -0.27655447  0.00000000   -0.00000000  0.00000000   -0.00000000 
0.00000000
  -0.00000000  0.00000000   -0.27655447  0.00000000    0.00000000 
0.00000000
  -0.00000000  0.00000000    0.00000000  0.00000000   -0.27655447 
0.00000000
   2  2
   0.27657353  0.00000000    0.00000000  0.00000000    0.00000000 
0.00000000
  -0.00000000  0.00000000    0.27657353  0.00000000    0.00000000 
0.00000000
  -0.00000000  0.00000000   -0.00000000  0.00000000    0.27657353 
0.00000000

      Dielectric Tensor:

          13.806429681482          0.000000000000         -0.000000000000
           0.000000000000         13.806429681482         -0.000000000000
          -0.000000000000         -0.000000000000         13.806429681482

      Effective Charges E-U: Z_{alpha}{s,beta}

      atom #    1
          -0.075684611458          0.000000000000         -0.000000000000
           0.000000000000         -0.075684611458          0.000000000000
          -0.000000000000          0.000000000000         -0.075684611458
      atom #    2
          -0.075684611458         -0.000000000000         -0.000000000000
          -0.000000000000         -0.075684611458          0.000000000000
          -0.000000000000          0.000000000000         -0.075684611458

      Diagonalizing the dynamical matrix

      q = (    0.000000000   0.000000000   0.000000000 )

  **************************************************************************
      omega( 1) =       0.089782 [THz] =       2.994825 [cm-1]
  ( -0.418364  0.000000  0.344966  0.000000  0.453839  0.000000 )
  ( -0.418364  0.000000  0.344966  0.000000  0.453839  0.000000 )
      omega( 2) =       0.089782 [THz] =       2.994825 [cm-1]
  (  0.075065  0.000000  0.591377  0.000000 -0.380313  0.000000 )
  (  0.075065  0.000000  0.591377  0.000000 -0.380313  0.000000 )
      omega( 3) =       0.089782 [THz] =       2.994825 [cm-1]
  ( -0.565099 -0.000000 -0.176836 -0.000000 -0.386513 -0.000000 )
  ( -0.565099 -0.000000 -0.176836 -0.000000 -0.386513 -0.000000 )
      omega( 4) =      15.294047 [THz] =     510.157877 [cm-1]
  (  0.489220  0.000000 -0.455114  0.000000 -0.231375  0.000000 )
  ( -0.489220  0.000000  0.455114  0.000000  0.231375  0.000000 )
      omega( 5) =      15.294047 [THz] =     510.157877 [cm-1]
  (  0.481628 -0.000000  0.517721 -0.000000 -0.000000 -0.000000 )
  ( -0.481628 -0.000000 -0.517721 -0.000000 -0.000000 -0.000000 )
      omega( 6) =      15.294047 [THz] =     510.157877 [cm-1]
  ( -0.169406  0.000000  0.157595  0.000000 -0.668181  0.000000 )
  (  0.169406  0.000000 -0.157595  0.000000  0.668181  0.000000 )
  **************************************************************************


-- 
___________________________________________________
Cristian Degli Esposti Boschi
CNR, CNISM, Unita' di Ricerca di Bologna, c/o
Dipartimento di Fisica, Universita' di Bologna
viale Berti-Pichat, 6/2, 40127, Bologna, Italia
tel. ++39 051 2095114   fax ++39 051 2095113
e-mail: cristian.degliesposti -AT- unibo.it
web:    http://www.df.unibo.it/fismat/theory
___________________________________________________