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Modulated and composite structures dictionary (msCIF) version 1.0.1

Category ATOM_SITE_ROT_FOURIER_PARAM

Name:
'_atom_site_rot_Fourier_param_[]'

Definition:

   Data items in the ATOM_SITE_ROT_FOURIER_PARAM category record
   details about the coefficients of the Fourier series used to
   describe the rotational component of the displacive modulation of
   a given rigid group. The translational part would appear in a
   separate list of items belonging to the
   ATOM_SITE_DISPLACE_FOURIER_PARAM category. The Fourier components
   are defined in the category ATOM_SITE_ROT_FOURIER and are listed
   separately.

Examples:

Example 1 - example corresponding to the one-dimensional incommensurately modulated structure of K~2~SeO~4~.
 
     loop_
         _atom_site_rot_Fourier_param_id
         _atom_site_rot_Fourier_param_cos
         _atom_site_rot_Fourier_param_sin
              SeO4_x_1    -4.2(1)   0.91(3)
              SeO4_y_1     4.3(1)   0.



Example 2 - extracted from Baudour & Sanquer [Acta Cryst. (1983), B39, 75-84]. Note the entry from the ATOM_SITES_ROT_FOURIER category to describe collective information relating to all the atom sites.
 
     _atom_sites_rot_Fourier_axes_description
     ;   a1 and a2 are respectively the long molecular axis
         and the axis normal to the mean molecular plane.
     ;
     loop_
         _atom_site_rot_Fourier_param_id
         _atom_site_rot_Fourier_param_modulus
         _atom_site_rot_Fourier_param_phase
              Ph1_a1_1  11.0(2)  0.
              Ph2_a1_1  11.0(2)  0.5
              Bph_a2_1   1.0(1)  0.25



Type: null

Category: category_overview