[Pw_forum] (no subject)

Eduardo Ariel Menendez P emenendez at macul.ciencias.uchile.cl
Tue Feb 14 22:33:06 CET 2006


Hello,

I have a strange situation. For a system of 32 Cd and 32 Te atoms y have
calculated the ground energy with pw.x and cp.x

For pw
!    total energy              = -4194.76510666 ryd
i. e., -2097.382 Ha

For cp
total energy =    -2097.04257

The difference is 0.005 Ha/atom, then it seems that I have convergence.
ekinc in cp is also small.
ekinc          ekin          epot          etot     tempp
0.02666     183.66406   -1213.20570    -960.95069       0.0
b.t.w, what is ekin? Is it the run average of ekinc?


The problem that does not let my sleep is that for CP I read
System Density [g/cm^3] :     5.8563
.................
Total stress (GPa)
     -102.55028826         0.41139812         0.07268107
        0.41139812      -103.87561021        -0.18220224
        0.07268108        -0.18220224      -102.86279720
but for pw
          total   stress  (ryd/bohr**3)                  (kbar)     P= 21.33
   0.00019794   0.00002107  -0.00003053         29.12      3.10     -4.49
   0.00002107   0.00011087  -0.00003514          3.10     16.31     -5.17
  -0.00003053  -0.00003514   0.00012620         -4.49     -5.17     18.57

Then, who can I believe?

These are the input files
 &CONTROL
                 calculation = 'cp' ,
                restart_mode = 'restart' ,
                      outdir = '/home/eduardo/Compilaciones/Espresso/MD-CP/' ,
                  pseudo_dir = '/home/eduardo/Compilaciones/Espresso/MD-CP/',
                      prefix = 'cdte64' ,
                          dt = 4.0,
                       nstep = 100,iprint=20,isave=20,
                      tstress=.true.,tprnfor=.true.,
    ndr=91, ndw=91,
 etot_conv_thr = 1.d-9,ekin_conv_thr = 1.d-5,
 /
 &SYSTEM
                       ibrav = 14,
                   celldm(1) = 24.4946,
                   celldm(2) = 1.0,celldm(3) = 1.0,celldm(4) = 0.0,celldm(5) = 0.0,celldm(6) = 0.0,
                         nat = 64,
                        ntyp = 2,
                     nbnd=288,nelec=576,nspin=1,
                     ecutwfc = 30.0 ,
                     ecutrho = 240 ,
                 occupations = 'fixed' ,
		xc_type = 'PBE',
                    smearing = 'fd' ,
                         nosym = .true.,
    nr1b=25 , nr2b=25 , nr3b=25 ,
   qcutz=150., q2sigma=2.0, ecfixed=24.0,
 /
 &ELECTRONS
    electron_dynamics='damp',electron_damping=0.2,
    emass=500.d0, emass_cutoff=3.d0,
  orthogonalization = 'ortho',
  ortho_eps = 5.d-8,
  ortho_max = 15,
  electron_velocities = 'zero',
  electron_temperature = 'not_controlled'
 /
 &IONS
    ion_dynamics='none',
    ion_radius(1)=1.0, ion_radius(2)=1.0,
             ion_temperature = 'rescaling' ,
                       tempw = 2000 ,
                        tolp = 1.D-2 ,
 /
&CELL
  cell_dynamics = 'none',
  cell_velocities = 'zero',
  press = 0.0d0,
  wmass = 70000.0d0
/

ATOMIC_SPECIES
   Cd  112.41000  Cd.pbe-van.UPF
   Te  127.60000  Te.pbe-rkkjus-d.UPF

ATOMIC_POSITIONS crystal
   Cd      0.799931907    0.974912544    0.697391927
   Cd      0.339731787    0.485213972    0.488653125
   Cd      0.326213429    0.979344037    0.953936392
   Cd      0.978723474    0.518658890    0.592764013
   Cd      0.512960735    0.225083702    0.205121248
   Cd      0.504718742    0.949695475    0.300711498
   Cd      0.528281712    0.460727001    0.945214043
   Cd      0.371675507    0.676544170    0.282806590
   Cd      0.329150304    0.022517629    0.742724558
   Cd      0.620086766    0.980168732    0.070357853
   Cd      0.410888793    0.640098908    0.077411417
   Cd      0.900000914    0.195415374    0.164073912
   Cd      0.142737788    0.802988157    0.295814360
   Cd      0.700835563    0.780238184    0.012946118
   Cd      0.965746574    0.273927387    0.749811767
   Cd      0.433591384    0.430872378    0.248205777
   Cd      0.353512363    0.392686878    0.009102935
   Cd      0.030806872    0.821852186    0.854504546
   Cd      0.256438307    0.792563151    0.076754873
   Cd      0.311716809    0.962012129    0.192918432
   Cd      0.801452499    0.280229074    0.894348353
   Cd      0.469099445    0.657689919    0.606255798
   Cd      0.923310403    0.735926292    0.050534466
   Cd      0.864922505    0.298235092    0.503667180
   Cd      0.473110345    0.840355934    0.099473451
   Cd      0.023003560    0.604166994    0.886398219
   Cd      0.033306065    0.802019466    0.478744543
   Cd      0.633762672    0.752830911    0.701276949
   Cd      0.160456487    0.085695753    0.429505853
   Cd      0.970333828    0.446302302    0.265849690
   Cd      0.166559738    0.451689978    0.706150745
   Cd      0.481729865    0.869961855    0.816958764
   Te      0.545419637    0.461788417    0.540644179
   Te      0.824494447    0.846560441    0.338108257
   Te      0.581822000    0.607706225    0.302282816
   Te      0.127474436    0.951149047    0.013009348
   Te      0.134564155    0.707972617    0.674908901
   Te      0.363501489    0.508832198    0.759528997
   Te      0.716705448    0.528102204    0.879270488
   Te      0.740153467    0.264048511    0.304963913
   Te      0.123130594    0.271798189    0.239442782
   Te      0.928535961    0.106132238    0.580554296
   Te      0.097787132    0.363801484    0.437662623
   Te      0.858266187    0.046642655    0.003033062
   Te      0.936424501    0.631195138    0.376781667
   Te      0.324476914    0.193844771    0.015340039
   Te      0.182531951    0.581862885    0.365474428
   Te      0.577495739    0.221237266    0.011022996
   Te      0.332403368    0.254487710    0.559232473
   Te      0.780209598    0.488873559    0.586767375
   Te      0.046525880    0.911410064    0.667752369
   Te      0.676579297    0.257794687    0.685827840
   Te      0.212187663    0.540764460    0.088827859
   Te      0.536330325    0.856113031    0.475234109
   Te      0.358640689    0.120924635    0.341589581
   Te      0.913344616    0.508030873    0.043675568
   Te      0.290133474    0.813533577    0.595525549
   Te      0.689952869    0.566294694    0.080938740
   Te      0.743331484    0.671509972    0.494435792
   Te      0.794130924    0.804183946    0.824547896
   Te      0.600429222    0.011752483    0.634246079
   Te      0.741465064    0.055758011    0.390921089
   Te      0.183887405    0.151777249    0.662226385
   Te      0.106564251    0.367940618    0.888589564

and for cp

 &CONTROL
                 calculation = 'md' ,
                restart_mode = 'from_scratch' ,
                      outdir = '.' ,
                  pseudo_dir = '.' ,
                      prefix = 'cdte64-ea' ,
                     tstress = .true. ,
                     tprnfor = .true. ,
                          dt = 10
 /
 &SYSTEM
                       ibrav = 1,
                   celldm(1) = 24.4946,
                         nat = 64,
                        ntyp = 2,
                     ecutwfc = 30.0 ,
                     ecutrho = 240 ,
                 occupations = 'smearing' ,
                     degauss = 0.02 ,
                    smearing = 'fermi-dirac' ,
 /
 &ELECTRONS
            electron_maxstep = 60,
                    conv_thr = 1.0D-7 ,
                 startingpot = 'atomic' ,
                 startingwfc = 'random' ,
                 mixing_mode = 'plain' ,
             diagonalization = 'david' ,
 /
 &IONS
                ion_dynamics = 'verlet' ,
                     upscale = 10.D0 ,
             ion_temperature = 'rescaling' ,
                       tempw = 2000 ,
                        tolp = 1.D-2 ,
 /
ATOMIC_SPECIES
   Cd  112.41000  Cd.pbe-van.UPF
   Te  127.60000  Te.pbe-rkkjus-d.UPF
ATOMIC_POSITIONS crystal
   Cd      0.799931907    0.974912544    0.697391927
   Cd      0.339731787    0.485213972    0.488653125
   Cd      0.326213429    0.979344037    0.953936392
   Cd      0.978723474    0.518658890    0.592764013
   Cd      0.512960735    0.225083702    0.205121248
   Cd      0.504718742    0.949695475    0.300711498
   Cd      0.528281712    0.460727001    0.945214043
   Cd      0.371675507    0.676544170    0.282806590
   Cd      0.329150304    0.022517629    0.742724558
   Cd      0.620086766    0.980168732    0.070357853
   Cd      0.410888793    0.640098908    0.077411417
   Cd      0.900000914    0.195415374    0.164073912
   Cd      0.142737788    0.802988157    0.295814360
   Cd      0.700835563    0.780238184    0.012946118
   Cd      0.965746574    0.273927387    0.749811767
   Cd      0.433591384    0.430872378    0.248205777
   Cd      0.353512363    0.392686878    0.009102935
   Cd      0.030806872    0.821852186    0.854504546
   Cd      0.256438307    0.792563151    0.076754873
   Cd      0.311716809    0.962012129    0.192918432
   Cd      0.801452499    0.280229074    0.894348353
   Cd      0.469099445    0.657689919    0.606255798
   Cd      0.923310403    0.735926292    0.050534466
   Cd      0.864922505    0.298235092    0.503667180
   Cd      0.473110345    0.840355934    0.099473451
   Cd      0.023003560    0.604166994    0.886398219
   Cd      0.033306065    0.802019466    0.478744543
   Cd      0.633762672    0.752830911    0.701276949
   Cd      0.160456487    0.085695753    0.429505853
   Cd      0.970333828    0.446302302    0.265849690
   Cd      0.166559738    0.451689978    0.706150745
   Cd      0.481729865    0.869961855    0.816958764
   Te      0.545419637    0.461788417    0.540644179
   Te      0.824494447    0.846560441    0.338108257
   Te      0.581822000    0.607706225    0.302282816
   Te      0.127474436    0.951149047    0.013009348
   Te      0.134564155    0.707972617    0.674908901
   Te      0.363501489    0.508832198    0.759528997
   Te      0.716705448    0.528102204    0.879270488
   Te      0.740153467    0.264048511    0.304963913
   Te      0.123130594    0.271798189    0.239442782
   Te      0.928535961    0.106132238    0.580554296
   Te      0.097787132    0.363801484    0.437662623
   Te      0.858266187    0.046642655    0.003033062
   Te      0.936424501    0.631195138    0.376781667
   Te      0.324476914    0.193844771    0.015340039
   Te      0.182531951    0.581862885    0.365474428
   Te      0.577495739    0.221237266    0.011022996
   Te      0.332403368    0.254487710    0.559232473
   Te      0.780209598    0.488873559    0.586767375
   Te      0.046525880    0.911410064    0.667752369
   Te      0.676579297    0.257794687    0.685827840
   Te      0.212187663    0.540764460    0.088827859
   Te      0.536330325    0.856113031    0.475234109
   Te      0.358640689    0.120924635    0.341589581
   Te      0.913344616    0.508030873    0.043675568
   Te      0.290133474    0.813533577    0.595525549
   Te      0.689952869    0.566294694    0.080938740
   Te      0.743331484    0.671509972    0.494435792
   Te      0.794130924    0.804183946    0.824547896
   Te      0.600429222    0.011752483    0.634246079
   Te      0.741465064    0.055758011    0.390921089
   Te      0.183887405    0.151777249    0.662226385
   Te      0.106564251    0.367940618    0.888589564
K_POINTS gamma

The pseudo potential  Te.pbe-rkkjus-d.UPF was generated by me using the
utility of Espresso. Maybe thisis the problem. With it I
could reproduce bands, lattice constant and DOS for CdTe and TeO2 using
pw.x . The Cd pseudo was taken form the web table. I also tested it and
generated one myself, but the one of the table performs better (surprise
:-) ).

Hoping to sleep soon
Regards

And happy St Valentin !!

Eduardo A. Menendez Proupin
Department of Physics
Faculty of Science
University of Chile
Las Palmeras 3425
Ñuñoa, Santiago
Chile
Phone: 56+2+978 74 11
http://fisica.ciencias.uchile.cl/~emenendez/



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