[Pw_forum] A problem about relax

[oulihui666]

Dear pwscf users:
      I am now doing a large job of 'relax' calculation. The unit cell contains 20 atoms and vacuum. The job has been running for seven days. While the total energy is decreasing, the amount it decreases is approximately a constant. We calculated the Pt(111) surface with pwscf, we use a five-layer slab containing 20 Pt atoms,  the atoms in the bottom three layers are fixed, and the others are allowed to relax. The input file and structure can be found in below. However, calculated results indicated, the atoms in the top two layers are not inward or outward relaxation, but upward or downward relaxation,  Could you tell me whether the input file is correct or not? and the final structure is correct or not please?
Thanks a lot
Best wishes
Lihui Ou

 

&CONTROL

                 calculation = 'relax' ,

                restart_mode = 'from_scratch' ,

                      outdir = '/home/olh/tmp/' ,

                  pseudo_dir = '/home/olh/pseudo/' ,

                      prefix = 'Pt111_20' ,

                     tstress = .true. ,

                     tprnfor = .true. ,

 /

 &SYSTEM

                       ibrav = 4,

                           A = 5.549 ,

                           B = 5.549 ,

                           C = 21.062 ,

                       cosAB = -0.5 ,

                       cosAC = 0 ,

                       cosBC = 0 ,

                         nat = 20,

                        ntyp = 1,

                     ecutwfc = 70 ,

                     ecutrho = 0 ,

                 occupations = 'smearing' ,

                     degauss = 0.02 ,

                    smearing = 'gaussian' ,

 /

 &ELECTRONS

                    conv_thr = 1.0D-8 ,

                 mixing_beta = 0.7D0 ,

             diagonalization = 'david' ,

 /

 &IONS

 /

ATOMIC_SPECIES

   Pt  195.09000  Pt.pz-rrkjus.linux.UPF 

ATOMIC_POSITIONS angstrom 

   Pt     -0.000000000    0.000000000   -9.062000000    0  0  0 

   Pt     -0.000000000    2.775000000   -9.062000000    0  0  0 

   Pt      2.403000000   -1.387000000   -9.062000000    0  0  0 

   Pt      2.403000000    1.387000000   -9.062000000    0  0  0 

   Pt     -0.000000000   -0.000000000   -2.265000000    1  1  1 

   Pt     -0.000000000    2.775000000   -2.265000000    1  1  1 

   Pt      2.403000000   -1.387000000   -2.265000000    1  1  1 

   Pt      2.403000000    1.387000000   -2.265000000    1  1  1 

   Pt      1.602000000    0.000000000   -4.531000000    0  0  0 

   Pt      1.602000000    2.775000000   -4.531000000    0  0  0 

   Pt      4.005000000   -1.387000000   -4.531000000    0  0  0 

   Pt      4.005000000    1.387000000   -4.531000000    0  0  0 

   Pt      0.801000000    1.387000000   -6.796000000    0  0  0 

   Pt      0.801000000    4.162000000   -6.796000000    0  0  0 

   Pt      3.204000000    0.000000000   -6.796000000    0  0  0 

   Pt      3.204000000    2.775000000   -6.796000000    0  0  0 

   Pt      0.801000000    1.387000000   -0.000000000    1  1  1 

   Pt      0.801000000    4.162000000   -0.000000000    1  1  1 

   Pt      3.204000000   -0.000000000   -0.000000000    1  1  1 

   Pt      3.204000000    2.775000000   -0.000000000    1  1  1 

K_POINTS automatic 

  3 3 1   1 1 1 

 

--

======================================
Lihui Ou
PH.D Candidate in Electrochemistry                      
College of Chemistry and Molecular Science            
Wuhan University,430072,Hubei Province,China 
E-mail:oulihui666 at 126.com
======================================
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