Modulated Structures CIF Dictionary version 1.0

_cell_wave_vector_

Names

Category: cell_wave_vector

Data type: numb (with optional s.u. in parentheses)

Must appear in a looped list containing '_cell_wave_vector_seq_id'
Enumeration default: 0.0

Definition

    	
   Independent modulation wave vector(s) with which the whole
   diffraction pattern is indexed, expressed as fractions of the
   three reciprocal basis vectors of the reference structure. In
   the case of composites the modulation wave vectors of each
   subsystem are expressed in terms of the reciprocal basis of its
   corresponding reference structure. Their number must match
   _cell_modulation_dimension. In the case of composites described
   in a single data block, the wave
   vectors are expressed in the three-dimensional basis chosen as
   reference in _cell_reciprocal_basis_description which would
   correspond to the subsystem (if any) whose W matrix is the
   {(_cell_modulation_dimension + 3)*
   (_cell_modulation_dimension + 3)} unit matrix. In this case
   the wave vectors used to describe the modulation of each
   subsystem are referred to their own reciprocal basis via the W
   matrices (for details see _cell_subsystem_matrix_W_ and
   _atom_site_Fourier_wave_vector_).