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Electron density dictionary (rhoCIF) version 1.0.1

_atom_local_axes_atom2

Name:
'_atom_local_axes_atom2'

Definition:

   Specifies 'atom2' in the definition of a local axis frame.
   The definition employs three atom-site labels, 'atom0', 'atom1'
   and 'atom2', and two axis labels, 'ax1' and 'ax2', having values
   '+/-X', '+/-Y' or '+/-Z'. For the atom defined by
   '_atom_local_axes_atom_label', whose nuclear position is taken
   as the origin, local axis 'ax1' is the vector from the origin to
   atom0, axis 'ax2' is perpendicular to 'ax1' and lies in the
   plane of 'ax1' and a vector
   passing through the origin parallel to the vector atom1 -> atom2
   (its positive direction making an acute angle with the vector
   parallel to atom1 -> atom2), and a right-handed orthonormal
   vector triplet is formed from the vector product of these
   two vectors. In most cases, atom1 will be the same as the
   atom specified by _atom_local_axes_atom_label. One or more
   'dummy' atoms (with arbitrary labels) may be used in the
   vector definitions, specified with zero occupancy in the
   _atom_site_ description.  The values of *_atom0, *_atom1 and
   *_atom2 must be identical to values given in the
   _atom_site_label list.


Appears in list containing _atom_local_axes_atom_label

Must match data name_atom_site_label

Type: char

Category: atom_local_axes