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<div>Dear QE users <BR>
   Recently, I have done some calculation of BN sheet with hydrogen atoms adsorbed on it.  The problem is that when I let hydrogen atoms adsorb on the N atoms. The calculation is hard to converge. Although, I have changed mixing_beta and the number of K points. The problem have not been solved. Dose anyone have some experience on such kind of calculations? Any suggestions will be greatly appreciated. Here is my input file. <BR>
&CONTROL <BR>
     title = 'graphene layer' , <BR>
     calculation = 'relax' , <BR>
     restart_mode = 'restart' , <BR>
     outdir = './tmp' , <BR>
     pseudo_dir = '/lustre/ISSP2/tfcao/pseudo' , <BR>
     prefix = 'graphene' , <BR>
     tprnfor = .TRUE. , <BR>
     nstep = 400 , <BR>
 / <BR>
 &SYSTEM <BR>
     ibrav = 8 , <BR>
     a = 15.026832 , b = 13.014 , c = 15.0 , <BR>
     nat = 74 , <BR>
     ntyp = 3 , <BR>
     starting_magnetization(1) = 0.5 , <BR>
     occupations = 'smearing' , <BR>
     nosym = .TRUE. , <BR>
     degauss = 0.005 , <BR>
     smearing = 'mp' , <BR>
     nspin = 2 , <BR>
     ecutwfc = 30.0 , <BR>
     ecutrho = 300.0 , <BR>
 / <BR>
 &ELECTRONS <BR>
     conv_thr = 1.0d-7 , <BR>
     mixing_mode = 'local-TF' , <BR>
     mixing_beta = 0.1 , <BR>
     diagonalization = 'cg' , <BR>
 / <BR>
 &IONS <BR>
     ion_dynamics = 'bfgs' , <BR>
     pot_extrapolation = 'atomic' , <BR>
<BR>
/ <BR>
 ATOMIC_SPECIES <BR>
  B   10.811    B.pbe-n-van.UPF <BR>
  N   14.00674  N.pbe-rrkjus.UPF <BR>
  H   1.00000   H.pbe-rrkjus.UPF <BR>
ATOMIC_POSITIONS crystal <BR>
ATOMIC_POSITIONS crystal <BR>
 N   0.0000000       0.0000000      0.50000000  0  0  0 <BR>
 B   0.0000000      0.11111100      0.50000000 <BR>
 N  8.33330005E-02  0.16666700      0.50000000 <BR>
 B  8.33330005E-02  0.27777800      0.50000000 <BR>
 N   0.0000000      0.33333299      0.50000000 <BR>
 B   0.0000000      0.44444400      0.50000000 <BR>
 N  8.33330005E-02  0.50000000      0.50000000 <BR>
 B  8.33330005E-02  0.61111099      0.50000000 <BR>
 N   0.0000000      0.66666597      0.50000000 <BR>
 B   0.0000000      0.77777696      0.50000000 <BR>
 N  8.33330005E-02  0.83333296      0.50000000 <BR>
 B  8.33330005E-02  0.94444394      0.50000000 <BR>
 N  0.16666700       0.0000000      0.50000000 <BR>
 B  0.16666700      0.11111100      0.50000000 <BR>
 N  0.25000000      0.16666700      0.50000000 <BR>
 B  0.25000000      0.27777800      0.50000000 <BR>
 N  0.16666700      0.33333299      0.50000000 <BR>
 B  0.16666700      0.44444400      0.50000000 <BR>
 N  0.25000000      0.50000000      0.50000000 <BR>
 B  0.25000000      0.61111099      0.50000000 <BR>
 N  0.16666700      0.66666597      0.50000000 <BR>
 B  0.16666700      0.77777696      0.50000000 <BR>
 N  0.25000000      0.83333296      0.50000000 <BR>
 B  0.25000000      0.94444394      0.50000000 <BR>
 N  0.33333400       0.0000000      0.50000000 <BR>
 B  0.33333400      0.11111100      0.50000000 <BR>
 N  0.41666698      0.16666700      0.50000000 <BR>
 B  0.41666698      0.27777800      0.50000000 <BR>
 N  0.33333400      0.33333299      0.50000000 <BR>
 B  0.33333400      0.44444400      0.50000000 <BR>
 N  0.41666698      0.50000000      0.50000000 <BR>
 B  0.41666698      0.61111099      0.50000000 <BR>
 N  0.33333400      0.66666597      0.50000000 <BR>
 B  0.33333400      0.77777696      0.50000000 <BR>
 N  0.41666698      0.83333296      0.50000000 <BR>
 B  0.41666698      0.94444394      0.50000000 <BR>
 N  0.50000101       0.0000000      0.50000000 <BR>
 B  0.50000101      0.11111100      0.50000000 <BR>
 N  0.58333403      0.16666700      0.50000000 <BR>
 B  0.58333403      0.27777800      0.50000000 <BR>
 N  0.50000101      0.33333299      0.50000000 <BR>
 B  0.50000101      0.44444400      0.50000000 <BR>
 N  0.58333403      0.50000000      0.50000000 <BR>
 B  0.58333403      0.61111099      0.50000000 <BR>
 N  0.50000101      0.66666597      0.50000000 <BR>
 B  0.50000101      0.77777696      0.50000000 <BR>
 N  0.58333403      0.83333296      0.50000000 <BR>
 B  0.58333403      0.94444394      0.50000000 <BR>
 N  0.66666800       0.0000000      0.50000000 <BR>
 B  0.66666800      0.11111100      0.50000000 <BR>
 N  0.75000101      0.16666700      0.50000000 <BR>
 B  0.75000101      0.27777800      0.50000000 <BR>
 N  0.66666800      0.33333299      0.50000000 <BR>
 B  0.66666800      0.44444400      0.50000000 <BR>
 N  0.75000101      0.50000000      0.50000000 <BR>
 B  0.75000101      0.61111099      0.50000000 <BR>
 N  0.66666800      0.66666597      0.50000000 <BR>
 B  0.66666800      0.77777696      0.50000000 <BR>
 N  0.75000101      0.83333296      0.50000000 <BR>
 B  0.75000101      0.94444394      0.50000000 <BR>
 N  0.83333498       0.0000000      0.50000000 <BR>
 B  0.83333498      0.11111100      0.50000000 <BR>
 N  0.91666800      0.16666700      0.50000000 <BR>
 B  0.91666800      0.27777800      0.50000000 <BR>
 N  0.83333498      0.33333299      0.50000000 <BR>
 B  0.83333498      0.44444400      0.50000000 <BR>
 N  0.91666800      0.50000000      0.50000000 <BR>
 B  0.91666800      0.61111099      0.50000000 <BR>
 N  0.83333498      0.66666597      0.50000000 <BR>
 B  0.83333498      0.77777696      0.50000000 <BR>
 N  0.91666800      0.83333296      0.50000000 <BR>
 B  0.91666800      0.94444394      0.50000000 <BR>
 H  0.50000000      0.66666600      0.56900670 <BR>
 H  0.66666800      0.33333300      0.56900670 <BR>
K_POINTS {automatic} <BR>
8 8 1 0 0 0 <BR>
====================================================================== <BR>
Teng Fei Cao <BR>
======================================================================                                                                                                                                                                                      <BR>
    Research Laboratory for Computational Materials Sciences, <BR>
Instutue of Solid State Physics,the Chinese Academy of Sciences, <BR>
P.O.Box 1129, Hefei 230031, P.R.China <BR>
Tel: 86-551-5591464-326(office) <BR>
Fax: 86-551-5591434                                                                                                                                                                                                                                                                                                                                                     <BR>
   </div>


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