[QE-users] Stability issue in vc-relax for two different pseudo-potentials

Manoar Hossain manoarphy at niser.ac.in
Wed May 12 08:46:47 CEST 2021


Dear experts,

I am trying to do vc-relax for my 2D systems made of C, B and N. Two
different pseudo potentials gave me totally two different results, NORMCONS
LDA gave me unstable structure but ULTRASOFT LDA gave me otherwise.
Then I took the known 2D boron-nitride system to investigate further and
again I got two different outcomes (which I attached below).
Am I doing something wrong? or am I missing something?
If not then which one I should believe out of the twos.

Your help will be much appreciated.
Thanks in advance,

Regards,



-- 
Manoar Hossain
Research Scholar
School of Physical Sciences
National Institute of Science Education and Research (NISER)
Bhubaneswar, Jatni, Khurda, Odisha, 752050, INDIA
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20210512/7d14fc51/attachment.html>
-------------- next part --------------

----------------------------------------------------------------------
INPUT:
----------------------------------------------------------------------

&CONTROL
   prefix = 'bn5x5'
   calculation = 'vc-relax'
   title = 'vc-relax_calculation'
   restart_mode = 'from_scratch'
   pseudo_dir = '/home/mhossain/pseudo_potential/'
   outdir = './tmp'
   verbosity = 'high'
   tstress = .true.
   tprnfor = .true.
   etot_conv_thr = 1.0D-6
   forc_conv_thr = 1.0D-5
   nstep = 900
   wf_collect = .true.
 /
&SYSTEM
   ibrav = 0
   nat =   50
   ntyp =  2
   ecutwfc =  50.0
   ecutrho =  200.0
   occupations = 'smearing'
   degauss = 0.002
 /
&ELECTRONS
   conv_thr = 1.D-8
   mixing_beta = 0.3D0
   diagonalization = 'cg'
 /
&IONS
 /
&CELL
   cell_dofree = '2Dxy'
 /
ATOMIC_SPECIES
  B  10.8110   B.pz-vbc.UPF
  N  14.0067   N.pz-vbc.UPF
K_POINTS {automatic}
  6  6  1   0 0 0
CELL_PARAMETERS {angstrom}
  10.776594   6.221869   0.000000
  10.776594  -6.221869   0.000000
   0.000000   0.000000  11.000000
ATOMIC_POSITIONS {angstrom}
 B       1.43687916       1.12152101E-07   5.38600159    
 N       2.87375832       1.12152101E-07   5.48600197    
 B       3.59219837       1.24437380       5.48600197    
 N       5.02907658       1.24437380       5.58600235    
 B       5.74751663       2.48874760       5.48600197    
 N       7.18439674       2.48874760       5.48600197    
 B       7.90283394       3.73312163       5.48600197    
 N       9.33971596       3.73312163       5.38600159    
 B       10.0581532       4.97749519       5.48600197    
 N       11.4950314       4.97749519       5.58600235    
 B       3.59219837      -1.24437380       5.48600197    
 N       5.02907658      -1.24437380       5.48600197    
 B       5.74751663       1.12152101E-07   5.38600159    
 N       7.18439674       1.12152101E-07   5.58600235    
 B       7.90283394       1.24437380       5.48600197    
 N       9.33971596       1.24437380       5.48600197    
 B       10.0581532       2.48874760       5.48600197    
 N       11.4950314       2.48874760       5.58600235    
 B       12.2134724       3.73312163       5.48600197    
 N       13.6503506       3.73312163       5.38600159    
 B       5.74751663      -2.48874760       5.58600235    
 N       7.18439674      -2.48874760       5.48600197    
 B       7.90283394      -1.24437380       5.48600197    
 N       9.33971596      -1.24437380       5.58600235    
 B       10.0581532       1.12152101E-07   5.48600197    
 N       11.4950314       1.12152101E-07   5.38600159    
 B       12.2134724       1.24437380       5.58600235    
 N       13.6503506       1.24437380       5.38600159    
 B       14.3687916       2.48874760       5.48600197    
 N       15.8056698       2.48874760       5.58600235    
 B       7.90283394      -3.73312163       5.48600197    
 N       9.33971596      -3.73312163       5.48600197    
 B       10.0581532      -2.48874760       5.58600235    
 N       11.4950314      -2.48874760       5.48600197    
 B       12.2134724      -1.24437380       5.48600197    
 N       13.6503506      -1.24437380       5.58600235    
 B       14.3687916       1.12152101E-07   5.48600197    
 N       15.8056698       1.12152101E-07   5.48600197    
 B       16.5241127       1.24437380       5.48600197    
 N       17.9609909       1.24437380       5.48600197    
 B       10.0581532      -4.97749519       5.48600197    
 N       11.4950314      -4.97749519       5.58600235    
 B       12.2134724      -3.73312163       5.48600197    
 N       13.6503506      -3.73312163       5.48600197    
 B       14.3687916      -2.48874760       5.58600235    
 N       15.8056698      -2.48874760       5.48600197    
 B       16.5241127      -1.24437380       5.58600235    
 N       17.9609909      -1.24437380       5.38600159    
 B       18.6794281       1.12152101E-07   5.48600197    
 N       20.1163101       1.12152101E-07   5.58600235

----------------------------------------------------------------------
OUTPUT:
----------------------------------------------------------------------
Begin final coordinates
     new unit-cell volume =   7664.85213 a.u.^3 (  1135.81390 Ang^3 )
     density =      0.90708 g/cm^3

CELL_PARAMETERS (angstrom)
  10.442020917   6.021295880   0.000000000
   9.500163008  -4.410306891   0.000000000
   0.000000000   0.000000000  11.000000000

ATOMIC_POSITIONS (angstrom)
B             1.2567126289        0.2335600546        4.7681718106
N             2.5660987721        0.3759260211        4.2672758261
B             3.3451201276        1.4377954998        4.7684766783
N             4.6543180800        1.5803917048        4.2671749294
B             5.4336780675        2.6418948586        4.7687381379
N             6.7428872894        2.7845347029        4.2673591084
B             7.5220340655        3.8462572618        4.7686357844
N             8.8312441054        3.9886274619        4.2672566715
B             9.6103115573        5.0506532608        4.7680504968
N            10.9196795639        5.1929531062        4.2670266094
B             3.2748325243       -0.8531042412        4.1802964433
N             4.6753199528       -0.8686899363        4.3408435755
B             5.3630777888        0.3513451800        4.1805998703
N             6.7635208781        0.3356243453        4.3411785721
B             7.4515635381        1.5554751391        4.1804517244
N             8.8520659312        1.5395476533        4.3403479264
B             9.5399814099        2.7596039237        4.1800442285
N            10.9405361877        2.7438699752        4.3400745935
B            11.6284227621        3.9639085622        4.1799970214
N            13.0289136825        3.9481241295        4.3401984643
B             5.1404340188       -1.6755299279        5.4110901035
N             6.3990918603       -1.4455456708        5.9998720598
B             7.2285535609       -0.4709665886        5.4116501543
N             8.4877369424       -0.2413738224        5.9994486230
B             9.3172256137        0.7328534526        5.4107145848
N            10.5764176162        0.9622957563        5.9984799749
B            11.4058416497        1.9367949529        5.4101131189
N            12.6649805849        2.1661677626        5.9980304469
B            13.4943215189        3.1409537427        5.4101086831
N            14.7532433855        3.3705474689        5.9984632011
B             6.9820319847       -2.4563731942        6.8066452818
N             8.3707867233       -2.4517097200        7.0585343908
B             9.0704700883       -1.2521020408        6.8064567603
N            10.4591628720       -1.2474708012        7.0585008334
B            11.1590075203       -0.0480811479        6.8060136056
N            12.5476306814       -0.0433676281        7.0585004548
B            13.2474698471        1.1560021077        6.8059022493
N            14.6360625804        1.1608111687        7.0586730233
B            15.3357944059        2.3602726933        6.8061142212
N            16.7244403360        2.3652922946        7.0586321312
B             8.9824895798       -3.5125907302        6.3309414921
N            10.2942236794       -3.3744060189        5.8372140866
B            11.0709936912       -2.3086292419        6.3313909813
N            12.3827705221       -2.1705001576        5.8378114151
B            13.1596441696       -1.1046992263        6.3318423609
N            14.4715584334       -0.9668002716        5.8384681925
B            15.2481184037        0.0994813356        6.3320239880
N            16.5597300638        0.2379627825        5.8380001542
B            17.3363014442        1.3042846842        6.3313437322
N            18.6477193473        1.4428508790        5.8369223827
End final coordinates
-------------- next part --------------

----------------------------------------------------------------------
INPUT
----------------------------------------------------------------------

&CONTROL
   prefix = 'bn5x5'
   calculation = 'vc-relax'
   title = 'vc-relax_calculation'
   restart_mode = 'from_scratch'
   pseudo_dir = '/home/mhossain/pseudo_potential/'
   outdir = './tmp'
   verbosity = 'high'
   tstress = .true.
   tprnfor = .true.
   etot_conv_thr = 1.0D-6
   forc_conv_thr = 1.0D-5
   nstep = 900
   wf_collect = .true.
 /
&SYSTEM
   ibrav = 0
   nat =   50
   ntyp =  2
   ecutwfc =  50.0
   ecutrho =  400.0
   occupations = 'smearing'
   degauss = 0.002
 /
&ELECTRONS
   conv_thr = 1.D-8
   mixing_beta = 0.1D0
   diagonalization = 'cg'
 /
&IONS
 /
&CELL
   cell_dofree = '2Dxy'
 /
ATOMIC_SPECIES
  B  10.8110   B.pz-n-rrkjus_psl.0.1.UPF
  N  14.0067   N.pz-n-rrkjus_psl.0.1.UPF
K_POINTS {automatic}
  6  6  1   0 0 0
CELL_PARAMETERS {angstrom}
  10.775810000   6.221410000   0.000000000
  10.775810000  -6.221410000   0.000000000
   0.000000000   0.000000000  11.000000000
ATOMIC_POSITIONS {angstrom}
B             1.4367861559       -0.0001216996        5.4972165773
N             2.8735300736       -0.0001539411        5.4983098688
B             3.5919269794        1.2441554309        5.5014177296
N             5.0286609776        1.2441694106        5.5003051090
B             5.7470144279        2.4885570383        5.4992979728
N             7.1837748697        2.4885743668        5.4952164430
B             7.9022852618        3.7328348839        5.4937568113
N             9.3390602401        3.7328282737        5.4910149204
B            10.0573311183        4.9771469810        5.4931171322
N            11.4940544584        4.9770795209        5.4914226164
B             3.5919219676       -1.2444996450        5.4967536888
N             5.0287004702       -1.2444419325        5.5001411452
B             5.7470963562       -0.0002255097        5.5007575049
N             7.1839435263       -0.0000780164        5.5016166021
B             7.9022392798        1.2442800414        5.4979459247
N             9.3390193023        1.2442900733        5.4972916759
B            10.0574627400        2.4885325288        5.4917453341
N            11.4941818871        2.4885094230        5.4898466479
B            12.2124506398        3.7327869962        5.4912978067
N            13.6491756333        3.7327755244        5.4934006154
B             5.7471597764       -2.4887299479        5.5010312491
N             7.1839917079       -2.4885717031        5.5053740427
B             7.9024113878       -1.2443022743        5.5045226849
N             9.3391913674       -1.2442186885        5.5076929983
B            10.0575342723        0.0001218394        5.5031697142
N            11.4942012683        0.0001511885        5.5034628697
B            12.2126321966        1.2444018521        5.4959523163
N            13.6493867751        1.2443334840        5.4969228375
B            14.3676658171        2.4885546663        5.4957955268
N            15.8044522235        2.4885713025        5.4985449184
B             7.9024379595       -3.7328128912        5.5059918681
N             9.3391962837       -3.7327826072        5.5087941635
B            10.0576233659       -2.4884663401        5.5106270928
N            11.4943657192       -2.4884302421        5.5105619979
B            12.2125855156       -1.2440628536        5.5075275697
N            13.6492897969       -1.2441423293        5.5032439955
B            14.3677370956        0.0001009373        5.4993720220
N            15.8044942197        0.0000216584        5.4995334680
B            16.5228813617        1.2443009749        5.5009406026
N            17.9596728740        1.2443822316        5.5022497549
B            10.0575114438       -4.9771150824        5.5033160365
N            11.4942789617       -4.9771339761        5.5044525664
B            12.2126494637       -3.7328147363        5.5076362568
N            13.6493863550       -3.7328851604        5.5054266203
B            14.3676006840       -2.4884061785        5.5033046093
N            15.8043760865       -2.4885599665        5.5003200183
B            16.5228629268       -1.2442831299        5.4987691638
N            17.9597124792       -1.2442491052        5.4965069251
B            18.6780213632        0.0000733819        5.4990562544
N            20.1148290960        0.0000705882        5.4981288900

----------------------------------------------------------------------
OUTPUT
----------------------------------------------------------------------
Begin final coordinates
     new unit-cell volume =   9953.60596 a.u.^3 (  1474.97223 Ang^3 )
     density =      0.69850 g/cm^3

CELL_PARAMETERS (angstrom)
  10.776084968   6.221572523   0.000000000
  10.776084806  -6.221572242   0.000000000
   0.000000000   0.000000000  11.000000000

ATOMIC_POSITIONS (angstrom)
B             1.4368243426        0.0000176848        5.4995216472
N             2.8736320591        0.0000188746        5.4991298136
B             3.5920396512        1.2443459687        5.5004738880
N             5.0288581113        1.2443416620        5.4999032964
B             5.7472658564        2.4886457644        5.4996284930
N             7.1840912314        2.4886424811        5.4983875989
B             7.9024916247        3.7329432016        5.4973135848
N             9.3393082016        3.7329414559        5.4966408511
B            10.0577049429        4.9772567126        5.4977694206
N            11.4945155678        4.9772593867        5.4979758576
B             3.5920376291       -1.2442733144        5.4979536841
N             5.0288433638       -1.2442949248        5.4991017655
B             5.7472517381        0.0000434061        5.5000559221
N             7.1840601570        0.0000162639        5.5012454630
B             7.9024786159        1.2443215239        5.4994132939
N             9.3392979303        1.2443124466        5.4986628318
B            10.0577028956        2.4886174054        5.4974373865
N            11.4945244867        2.4886235693        5.4976088681
B            12.2129165774        3.7329488598        5.4972229035
N            13.6497327402        3.7329511379        5.4967947627
B             5.7472344997       -2.4886000177        5.5005282295
N             7.1840334213       -2.4886280578        5.5031223385
B             7.9024424265       -1.2443037720        5.5027911033
N             9.3392579165       -1.2443253813        5.5029186265
B            10.0576706118       -0.0000202589        5.5003944937
N            11.4944987150       -0.0000168471        5.4998070731
B            12.2129020898        1.2442911981        5.4986767011
N            13.6497182929        1.2443089744        5.4990089490
B            14.3681194076        2.4886358372        5.4981057683
N            15.8049207986        2.4886344565        5.4994268334
B             7.9024325775       -3.7329420519        5.5025916117
N             9.3392472694       -3.7329599178        5.5033094924
B            10.0576496555       -2.4886401305        5.5032727965
N            11.4944637815       -2.4886414222        5.5027912526
B            12.2128900672       -1.2443401340        5.5018531257
N            13.6497026694       -1.2443137395        5.5025102619
B            14.3681176923       -0.0000215551        5.5006855836
N            15.8049281618        0.0000015328        5.4999946192
B            16.5233255052        1.2443130803        5.4999303092
N            17.9601346366        1.2443062101        5.5005232133
B            10.0576690985       -4.9772613474        5.5015012009
N            11.4944733661       -4.9772580255        5.5015322540
B            12.2128945806       -3.7329449989        5.5024371747
N            13.6496989647       -3.7329275948        5.5022283848
B            14.3681260069       -2.4886378114        5.5021330514
N            15.8049446533       -2.4886134185        5.5004726202
B            16.5233455615       -1.2443216084        5.4993781464
N            17.9601630033       -1.2443157126        5.4976809510
B            18.6785530401       -0.0000037707        5.4989932834
N            20.1153643645       -0.0000096277        5.4992603789
End final coordinates


More information about the users mailing list