old_contents: #!/usr/bin/env python
  #
  # Author: Qiming Sun <osirpt.sun@gmail.com>
  #
  
  '''
  Ghost atom has nuclear charge 0
  
  The global basis set assignment such as ``basis = "sto3g"`` cannot be used on
  ghost atom.  One needs explicitly assign basis for ghost atom using eg
  :func:`gto.basis.load`.
  '''
  
  from pyscf import gto
  
  mol = gto.M(
      atom = 'C 0 0 0; ghost 0 0 2',
      basis = {'C': 'sto3g', 'ghost': gto.basis.load('sto3g', 'H')}
  )
  
  #
  # Add "ghost" as prefix for the ghost atom.  In this input, the basis set of the
  # unmodified atom is applied for the ghost atom.  In the following example,
  # ghost-O uses the O 6-31G basis.
  #
  mol = gto.M(atom='''
  ghost-O     0.000000000     0.000000000     2.500000000
  ghost_H    -0.663641000    -0.383071000     3.095377000
  ghost:H     0.663588000     0.383072000     3.095377000
  O     1.000000000     0.000000000     2.500000000
  H    -1.663641000    -0.383071000     3.095377000
  H     1.663588000     0.383072000     3.095377000
  ''', basis='631g')
  
  
new_contents: #!/usr/bin/env python
  #
  # Author: Qiming Sun <osirpt.sun@gmail.com>
  #
  
  '''
  Ghost atom has nuclear charge 0
  
  The global basis set assignment such as ``basis = "sto3g"`` cannot be used on
  ghost atom.  One needs explicitly assign basis for ghost atom using eg
  :func:`gto.basis.load`.
  '''
  
  from pyscf import gto
  
  mol = gto.M(
      atom = 'C 0 0 0; ghost 0 0 2',
      basis = {'C': 'sto3g', 'ghost': gto.basis.load('sto3g', 'H')}
  )
  
  #
  # Specify diffierent basis for different ghost atoms
  #
  mol = gto.M(atom='''
  ghost1     0.000000000     0.000000000     2.500000000
  ghost2    -0.663641000    -0.383071000     3.095377000
  ghost2     0.663588000     0.383072000     3.095377000
  O     1.000000000     0.000000000     2.500000000
  H    -1.663641000    -0.383071000     3.095377000
  H     1.663588000     0.383072000     3.095377000
  ''',
              basis={'ghost1':gto.basis.load('sto3g', 'O'),
                     'ghost2':gto.basis.load('631g', 'H'),
                     'O':'631g', 'H':'631g'}
  )
  
  
  #
  # Add "ghost" as prefix for the ghost atom.  In this input, the atoms prefixed
  # with ghost are ghost atoms.  Their charges are zero.  However, the basis set
  # of the unmodified atom is applied for the ghost atom.  In the following
  # example, ghost-O uses the 6-31G basis of oxygen atom.
  #
  mol = gto.M(atom='''
  ghost-O     0.000000000     0.000000000     2.500000000
  ghost_H    -0.663641000    -0.383071000     3.095377000
  ghost:H     0.663588000     0.383072000     3.095377000
  O     1.000000000     0.000000000     2.500000000
  H    -1.663641000    -0.383071000     3.095377000
  H     1.663588000     0.383072000     3.095377000
  ''', basis='631g')
  
  
subject: Update examples for input with ghost atoms