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Modulated and composite structures dictionary (msCIF) version 1.0.1

_atom_sites_modulation_global_phase_t_

Names:
'_atom_sites_modulation_global_phase_t_1' '_atom_sites_modulation_global_phase_t_2' '_atom_sites_modulation_global_phase_t_3' '_atom_sites_modulation_global_phase_t_4' '_atom_sites_modulation_global_phase_t_5' '_atom_sites_modulation_global_phase_t_6' '_atom_sites_modulation_global_phase_t_7' '_atom_sites_modulation_global_phase_t_8'

Definition:

   The initial phases, in cycles, of the modulation waves. For
   incommensurate structures they are irrelevant. However, they are
   essential for the description of commensurate structures within
   the superspace formalism, since they determine the space group
   of the commensurate superstructure [see Perez-Mato,
   Madariaga, Zu\~niga & Garcia Arribas (1987) or van
   Smaalen (1995)]. Note that for composites described
   using a single data block, the initial phases for each subsystem
   are derived using the W matrices (see _cell_subsystem_matrix_W_)
   from a unique set of global phases whose values are assigned to
   _atom_sites_modulation_global_phase_t_. Detailed information can
   be found in van Smaalen (1995).

   Ref: Perez-Mato, J. M., Madariaga, G., Zu\~niga, F. J. & Garcia
   Arribas, A. (1987). Acta Cryst. A43, 216-226. Smaalen, S. van
   (1995). Crystallogr. Rev. 4, 79-202.


The permitted range is -1.0 -> 1.0
Enumeration default: 0.0

Type: numb

Category: atom_sites_modulation