[Pw_forum] Cannot relax guanine molecule

[Wudmir Rojas]

I want to relax the guanine molecule but the relaxed structure show some
hydrogens detached from the main structure (see graph attached). It looks
like there is some sort of interaction between the periodic image even I
put it in a big box. Please, I will appreciate any suggestions.

Wudmir
PhD student, UK.
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-  -

&CONTROL

  title = ' guanine ',

  calculation = 'relax',

  restart_mode = 'from_scratch',

  tprnfor = .TRUE.,

  etot_conv_thr = 1.D-4,

  prefix = 'gua-relax-22-06-a'

  pseudo_dir = '~/espresso-pseudo/'

  outdir = './'



&SYSTEM

  ibrav = 0,

  celldm(1) = 18.897259886,

  nat = 16,

  ntyp = 4

  ecutwfc = 25.0,

  ecutrho = 200.0,

  occupations='smearing',

  smearing='gaussian',

  degauss=0.01

/

 &ELECTRONS

/

 &IONS

/

 ATOMIC_SPECIES

C  12.0107    C.pbe-mt_fhi.UPF

O  15.9994    O.pbe-mt_fhi.UPF

H  1.00794    H.pbe-mt_fhi.UPF

N  14.0067    N.pbe-mt_fhi.UPF



K_POINTS gamma



CELL_PARAMETERS (alat)

   8.000   0.000  0.00

   0.000   8.000  0.00

   0.000   0.000  8.00



ATOMIC_POSITIONS (angstrom)

N  0  0  0

C  0  0  1.440908

C  1.357081  0  1.91969

C  2.396462  0  0.987468

N  2.338369  0  -0.36805

C  1.102405  0  -0.817435

N  0.886377  0  -2.16208

N  1.849196  0  3.211795

C  3.148326  0  3.067635

N  3.542068  0  1.739303

H  -0.032303 0  -2.567841

H  1.694052  0  -2.761628

H  -0.932932  0  -0.393625

O  -1.065793  0  2.031419

H   3.871687  0  3.871397

H  4.482237  0  1.373635
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