[Pw_forum] Raman calculation using gamma point

Gana Natarajan gn203 at hermes.cam.ac.uk
Thu Apr 14 11:34:55 CEST 2005


Hello,
I am trying to calculate the Raman spectrum using the 2n+1 method for a 
small molecule with only the gamma point for k-point sampling.

There are two problems. First the nscf calculation with 'raman' as the 
keyword assumes there are 7 kpoints even though I specified only the 
gamma point in the input file.

Secondly, the raman code exits with this error




%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
      from phq_readin : error #         1
      cannot start from pw.x data file using Gamma-point tricks

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%



Gana




Here are the output files:




      Program RAMAN     v.2.1.1  starts ...
      Today is 14Apr2005 at 10:32: 5


      **********************************************
      *  Calculation of the Raman tensor by using  *
      *             the 2n+1 theorem               *
      **********************************************

      Reading file as4s4.save ...
      read complete

      Reading file as4s4.save ...
      read complete

      nbndx  =    22  nbnd   =    22  natomwfc =    32  npwx   =   33438
      nelec  =   44.00 nkb   =    32  ngl    =    2114


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
      from phq_readin : error #         1
      cannot start from pw.x data file using Gamma-point tricks

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

      stopping ...
2
-----------------------------------------------------------
nscf output:

    Program PWSCF     v.2.1    starts ...
      Today is 13Apr2005 at 18:43:46

      Ultrasoft (Vanderbilt) Pseudopotentials

      Current dimensions of program pwscf are:
      ntypx =10   npk =40000  lmax = 3
      nchix = 6  ndmx = 2000  nbrx =14 nqfx = 8

      gamma-point specific algorithms are used



      bravais-lattice index     =            1
      lattice parameter (a_0)   =      25.0000  a.u.
      unit-cell volume          =   15625.0000 (a.u.)^3
      number of atoms/cell      =            8
      number of atomic types    =            2
      kinetic-energy cutoff     =      40.0000  Ry
      charge density cutoff     =     160.0000  Ry
      convergence threshold     =      1.0E-10
      beta                      =       0.7000
      number of iterations used =            8  plain     mixing
      Exchange-correlation      =  SLA  PZ   NOGX NOGC (1100)
      iswitch =  0

      celldm(1)=  25.000000  celldm(2)=   0.000000  celldm(3)=   0.000000
      celldm(4)=   0.000000  celldm(5)=   0.000000  celldm(6)=   0.000000

      crystal axes: (cart. coord. in units of a_0)
                a(1) = (  1.000000  0.000000  0.000000 )
                a(2) = (  0.000000  1.000000  0.000000 )
                a(3) = (  0.000000  0.000000  1.000000 )

      reciprocal axes: (cart. coord. in units 2 pi/a_0)
                b(1) = (  1.000000  0.000000  0.000000 )
                b(2) = (  0.000000  1.000000  0.000000 )
                b(3) = (  0.000000  0.000000  1.000000 )


      PSEUDO 1 is As         zval =  5.0   lmax= 1   lloc= 0
      (in numerical form:   525 grid points, xmin =  0.00, dx = 0.0000)

      PSEUDO 2 is S          zval =  6.0   lmax= 1   lloc= 0
      (in numerical form:   475 grid points, xmin =  0.00, dx = 0.0000)

      atomic species   valence    mass     pseudopotential
         As             5.00    74.92000     As( 1.00)
         S              6.00    32.06500     S ( 1.00)

      No symmetry!

    Cartesian axes

      site n.     atom                  positions (a_0 units)
          1           As  tau(  1) = (  -1.1310585  -0.6149882   1.1713734 
)
          2           As  tau(  2) = (   1.6439121   0.6762321  -0.4021337 
)
          3           As  tau(  3) = (  -1.1310684   1.9674461   1.1713849 
)
          4           As  tau(  4) = (  -0.4302165   0.6762313  -1.9404116 
)
          5           S   tau(  5) = (   1.0481002  -0.9552012   0.9718893 
)
          6           S   tau(  6) = (  -1.5723807  -0.9552379  -0.9719943 
)
          7           S   tau(  7) = (   1.0480726   2.3077438   0.9718671 
)
          8           S   tau(  8) = (  -1.5723607   2.3077740  -0.9719750 
)

      number of k points=    7
                        cart. coord. in units 2pi/a_0
         k(   1) = (   0.0000000   0.0000000   0.0000000), wk =   2.0000000
         k(   2) = (   0.0010000   0.0000000   0.0000000), wk =   0.0000000
         k(   3) = (   0.0000000   0.0010000   0.0000000), wk =   0.0000000
         k(   4) = (   0.0000000   0.0000000   0.0010000), wk =   0.0000000
         k(   5) = (  -0.0010000   0.0000000   0.0000000), wk =   0.0000000
         k(   6) = (   0.0000000  -0.0010000   0.0000000), wk =   0.0000000
         k(   7) = (   0.0000000   0.0000000  -0.0010000), wk =   0.0000000

      G cutoff = 2533.0296  ( 267069 G-vectors)     FFT grid: (108,108,108)

      nbndx  =    88  nbnd   =    22  natomwfc =    32  npwx   =   33438
      nelec  =   44.00 nkb   =    32  ngl    =    2114

      The initial potential is read from file      as4s4.pot
      Starting wfc are atomic

      total cpu time spent up to now is     51.85 secs

      Band Structure Calculation
      Davidson diagonalization with overlap
    WARNING:    21 eigenvalues not converged
    WARNING:    10 eigenvalues not converged
    WARNING:     2 eigenvalues not converged
    WARNING:     1 eigenvalues not converged
    WARNING:     1 eigenvalues not converged
    WARNING:     1 eigenvalues not converged
    WARNING:     6 eigenvalues not converged
    WARNING:     6 eigenvalues not converged
    WARNING:     5 eigenvalues not converged
    WARNING:     5 eigenvalues not converged
    WARNING:     5 eigenvalues not converged
    WARNING:     5 eigenvalues not converged
      ethr =  2.27E-13,  avg # of iterations = 43.0

      total cpu time spent up to now is    939.50 secs

      End of band structure calculation

           k = 0.0000 0.0000 0.0000     band energies (ev):

    -81.7281 -69.8032 -69.5652 -68.7499 -68.3035 -58.5941 -57.4439 -56.4295
    -55.0232 -53.6798 -52.0498 -51.7376 -51.3685 -50.7285 -50.6942 -46.5119
    -46.4414 -45.5423 -41.8052 -41.6101 -41.4442 -41.1883

           k = 0.0010 0.0000 0.0000     band energies (ev):

    -81.8135 -69.9484 -69.6069 -68.7708 -68.2203 -58.5855 -57.5106 -56.4846
    -54.8557 -53.6948 -52.0418 -51.7299 -51.3259 -50.6914 -50.6587 -46.5080
    -46.4362 -45.5451 -41.8021 -41.5957 -41.4405 -41.1953

           k = 0.0000 0.0010 0.0000     band energies (ev):

    -81.6709 -69.8841 -69.5571 -68.7407 -68.3668 -58.6012 -57.4858 -56.4628
    -54.9285 -53.6866 -52.0535 -51.7426 -51.4093 -50.7664 -50.7243 -46.5130
    -46.4440 -45.5264 -41.8046 -41.6036 -41.4468 -41.1645

           k = 0.0000 0.0000 0.0010     band energies (ev):

    -81.7779 -69.8898 -69.5923 -68.7609 -68.2644 -58.5733 -57.4854 -56.4638
    -54.9290 -53.6753 -52.0474 -51.7340 -51.3496 -50.7125 -50.6769 -46.5098
    -46.4329 -45.5810 -41.8067 -41.6218 -41.4438 -41.0034

           k =-0.0010 0.0000 0.0000     band energies (ev):

    -81.6825 -69.7045 -69.5213 -68.7439 -68.3646 -58.6029 -57.3911 -56.3870
    -55.1758 -53.6667 -52.0576 -51.7458 -51.4060 -50.7639 -50.7241 -46.5157
    -46.4464 -45.5394 -41.8082 -41.6251 -41.4476 -41.0284

           k = 0.0000-0.0010 0.0000     band energies (ev):

    -81.8712 -69.7568 -69.5771 -68.7901 -68.1934 -58.5873 -57.4077 -56.4009
    -55.1121 -53.6733 -52.0458 -51.7338 -51.3168 -50.6867 -50.6524 -46.5111
    -46.4384 -45.5578 -41.8058 -41.6167 -41.4415 -41.0124

           k = 0.0000 0.0000-0.0010     band energies (ev):

    -81.6936 -69.7345 -69.5372 -68.7455 -68.3332 -58.6174 -57.4078 -56.4003
    -55.1114 -53.6844 -52.0522 -51.7417 -51.3851 -50.7440 -50.7092 -46.5146
    -46.4487 -45.5010 -41.8038 -41.5991 -41.4446 -40.9939

      Forces acting on atoms (Ry/au):

      atom   1 type  1   force =     0.14042728    0.15921601    1.09357842
      atom   2 type  1   force =     0.44830706    0.31380250   -0.05804306
      atom   3 type  1   force =    -0.17737579   -0.59532097    1.27554776
      atom   4 type  1   force =    -0.01787603   -0.06295173    0.15941767
      atom   5 type  2   force =     0.44740274   -1.43268615   -1.10852928
      atom   6 type  2   force =    -2.51102577   -2.60073973   -0.45287883
      atom   7 type  2   force =     0.44751222    1.63835904   -1.10916873
      atom   8 type  2   force =     1.22262829    2.58032101    0.20007604

      Total force =     5.714003     Total SCF correction =     0.000000

      Writing file     as4s4.save for program phonon

      PWSCF        : 16m 4.22s CPU time

      init_run     :    51.83s CPU
      electrons    :   887.65s CPU
      forces       :     7.56s CPU

      electrons    :   887.65s CPU
      c_bands      :   887.61s CPU
      sum_band     :    17.11s CPU

      c_bands      :   887.61s CPU
      init_us_2    :     3.35s CPU (      28 calls,   0.120 s avg)
      cegterg      :   884.36s CPU (      18 calls,  49.131 s avg)

      sum_band     :    17.11s CPU

      cegterg      :   884.36s CPU (      18 calls,  49.131 s avg)
      h_psi        :   758.70s CPU (     326 calls,   2.327 s avg)
      g_psi        :     4.87s CPU (     301 calls,   0.016 s avg)
      overlap      :    55.12s CPU (     301 calls,   0.183 s avg)
      cdiaghg      :     1.10s CPU (     308 calls,   0.004 s avg)
      update       :    64.89s CPU (     301 calls,   0.216 s avg)
      last         :    29.36s CPU (      55 calls,   0.534 s avg)

      h_psi        :   758.70s CPU (     326 calls,   2.327 s avg)
      init         :     6.90s CPU (     326 calls,   0.021 s avg)
      add_vuspsi   :    18.07s CPU (     326 calls,   0.055 s avg)

      General routines
      cft3         :     0.71s CPU (       3 calls,   0.236 s avg)
      cft3s        :   528.30s CPU (    3855 calls,   0.137 s avg)
      davcio       :     2.25s CPU (      46 calls,   0.049 s avg)




^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Gana Natarajan
Room 225
Department of Chemistry
Lensfield Road
Cambridge CB2 1EW
United Kingdom
Tel: +44 -(01223) 336 532
Fax: +44- (01223) 336 362


















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