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Electron density dictionary (rhoCIF) version 1.0.1




   Specifies 'atom1' 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