**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_).

Appears in list containing _cell_wave_vector_seq_id

Enumeration default: 0.0

**Type:** numb

**Category:** cell_wave_vector

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