Exemple #1
0
    def gen_super(self, grain=None, rbt=None, sup_v=6, sup_bxv=2, rcut=2.0):
        """ :method:`gen_super` Creates a :class:SubGrainBoundary super cell according to
        conventions described in Rittner and Seidman (PRB 54 6999).

        Args:
          grain(:class:`ase.Atoms`): atoms object passed from gen_super_rbt.
          rbt (list): rigid body translation as fractional translations of the supercell.
          sup_v(int): Size of supercell along v.
          sup_bxv(int): Size of supercell along boundary_plane_normal crossed with v.
          rcut(float): Atom deletion criterion in angstrom.
        """
        io = ImeallIO()
        if rbt == None:
            x = Atoms('{0}.xyz'.format(os.path.join(self.grain_dir, self.gbid)))
        else:
            x = Atoms(grain)

        struct_dir = os.path.join(self.grain_dir, 'structs')
        self.name = '{0}_v{1}bxv{2}_tv{3}bxv{4}_d{5}z'.format(self.gbid,
        str(sup_v), str(sup_bxv), '0.0', '0.0', str(rcut))
#TODO fix this so it is more transparent.
#if rcut = 0 then only a super cell is generated with no deletion of atoms.
        if rcut > 0.0:
            x.set_cutoff(2.4)
            x.calc_connect()
            x.calc_dists()
            rem = []
            u = np.zeros(3)
            for i in range(x.n):
                for n in range(x.n_neighbours(i)):
                    j = x.neighbour(i, n, distance=3.0, diff=u)
                    if x.distance_min_image(i,j) < rcut and j != i:
                        rem.append(sorted([j,i]))
            rem = list(set([a[0] for a in rem]))
            if len(rem) > 0:
                x.remove_atoms(rem)
            else:
                print 'No duplicate atoms in list.'
        else:
            x = x*(sup_v, sup_bxv, 1)
            x.set_scaled_positions(x.get_scaled_positions())

        if rbt == None:
            self.struct_file = self.name
            self.subgrain_dir = io.make_dir(self.calc_dir, self.name)
            try:
                with open('{0}/subgb.json'.format(self.subgrain_dir), 'r') as f:
                    j_dict = json.load(f)
            except IOError:
                j_dict             = {}

            j_dict['name']       = self.name
            j_dict['param_file'] = self.param_file
            j_dict['rbt']        = [0.0, 0.0]
            j_dict['rcut']       = rcut

            with open('{0}/subgb.json'.format(self.subgrain_dir), 'w') as f:
                json.dump(j_dict, f, indent=2)
        else:
            return sup_v, sup_bxv, x
Exemple #2
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def del_atoms(x=None):
  rcut = 2.0
  #x = Atoms('crack.xyz')
  if x == None:
    x = Atoms('1109337334_frac.xyz')
  else:
    pass
  x.set_cutoff(3.0)
  x.calc_connect()
  x.calc_dists()
  rem=[]
  r = farray(0.0)
  u = fzeros(3)
  print len(x)
  for i in frange(x.n):
    for n in frange(x.n_neighbours(i)):
      j = x.neighbour(i, n, distance=3.0, diff=u)
      if x.distance_min_image(i, j) < rcut and j!=i:
        rem.append(sorted([j,i]))
    if i%10000==0: print i
  rem = list(set([a[0] for a in rem]))
  if len(rem) > 0:
    print rem
    x.remove_atoms(rem)
  else:
    print 'No duplicate atoms in list.'
  x.write('crack_nodup.xyz')
  return x
Exemple #3
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    def delete_atoms(self, grain=None, rcut=2.0):
        """
        Delete atoms below a certain distance threshold.

        Args:
          grain(:class:`quippy.Atoms`): Atoms object of the grain.
          rcut(float): Atom deletion criterion.

        Returns:
          :class:`quippy.Atoms` object with atoms nearer than deletion criterion removed.
        """
        io = ImeallIO()
        if grain == None:
            x = Atoms('{0}.xyz'.format(os.path.join(self.grain_dir,
                                                    self.gbid)))
        else:
            x = Atoms(grain)
        x.set_cutoff(2.4)
        x.calc_connect()
        x.calc_dists()
        rem = []
        u = fzeros(3)
        for i in frange(x.n):
            for n in frange(x.n_neighbours(i)):
                j = x.neighbour(i, n, distance=3.0, diff=u)
                if x.distance_min_image(i, j) < rcut and j != i:
                    rem.append(sorted([j, i]))
        rem = list(set([a[0] for a in rem]))
        if len(rem) > 0:
            x.remove_atoms(rem)
        else:
            print 'No duplicate atoms in list.'
        if grain == None:
            self.name = '{0}_d{1}'.format(self.gbid, str(rcut))
            self.subgrain_dir = io.make_dir(self.calc_dir, self.name)
            self.struct_file = gbid + '_' + 'n' + str(
                len(rem)) + 'd' + str(rcut)
            x.write('{0}.xyz'.format(
                os.path.join(self.subgrain_dir, self.struct_file)))
            return len(rem)
        else:
            return x
Exemple #4
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#ats.wrap()
ats.write('crackH.xyz')
ats = None
ats = Atoms('crackH.xyz')
ats.set_cutoff(2.4)
ats.calc_connect()
ats.calc_dists()
filter_mask = (ats.get_atomic_numbers()==1)
h_atoms     = ats.select(filter_mask, orig_index=True)
rem=[]
u = np.zeros(3)
for i in h_atoms.orig_index:
  print 'hindex', i
  print 'nneighbs', ats.n_neighbours(i)
  for n in range(ats.n_neighbours(i)):
    j = ats.neighbour(i, n+1, distance=2.4, diff=u)
    print 'neighb index', j
    if ats.distance_min_image(i,j) < 1.1 and j!=i:
      rem.append(i)
rem = list(set(rem))
if len(rem) > 0:
  print 'Removing {} H atoms'.format(len(rem))
  ats.remove_atoms(rem)
else:
  print 'No H atoms closer than threshold.'
#Now a little housekeeping. In the vicinity of a cracktip
#Delaunay can go a little haywire. We remove any H that is far too close to an Fe atom
# |h-fe| < 1.1. and we remove the vacuum Hs
ats.write('crackH.xyz')
h_atoms = sum((ats.get_atomic_numbers() ==1))
zlen    = ats.get_cell()[2,2]