data_1008846
_chemical_name_systematic          'Trisodium dichromium triphosphorus(V) oxide'
_chemical_formula_structural       'Na3 Cr2 P3 O12'
_chemical_formula_sum              'Cr2 Na3 O12 P3'
_publ_section_title
;
Neutron scattering and diffraction study of Na3 Cr2 P3 O12, Na Zr2 P3
O12 and Na3 Zr Mg P3 O12
;
loop_
_publ_author_name
  'Lucazeau, G'
  'Barj, M'
  'Soubeyroux, J L'
  'Dianoux, A J'
  'Delmas, C'
_journal_name_full                 'Solid State Ionics'
_journal_coden_ASTM                SSIOD3
_journal_volume                    1819
_journal_year                      1986
_journal_page_first                959
_journal_page_last                 963
_cell_length_a                     8.6476(2)
_cell_length_b                     8.6476(2)
_cell_length_c                     21.6169(6)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  120
_cell_volume                       1400.0
_cell_formula_units_Z              6
_symmetry_space_group_name_H-M     'R -3 c H'
_symmetry_Int_Tables_number        167
_symmetry_cell_setting             trigonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-y,x-y,z'
  'y-x,-x,z'
  '-y,-x,1/2+z'
  'x,x-y,1/2+z'
  'y-x,y,1/2+z'
  '-x,-y,-z'
  'y,y-x,-z'
  'x-y,x,-z'
  'y,x,1/2-z'
  '-x,y-x,1/2-z'
  'x-y,-y,1/2-z'
  '1/3+x,2/3+y,2/3+z'
  '2/3+x,1/3+y,1/3+z'
  '1/3-y,2/3+x-y,2/3+z'
  '2/3-y,1/3+x-y,1/3+z'
  '1/3-x+y,2/3-x,2/3+z'
  '2/3-x+y,1/3-x,1/3+z'
  '1/3-y,2/3-x,1/6+z'
  '2/3-y,1/3-x,5/6+z'
  '1/3+x,2/3+x-y,1/6+z'
  '2/3+x,1/3+x-y,5/6+z'
  '1/3-x+y,2/3+y,1/6+z'
  '2/3-x+y,1/3+y,5/6+z'
  '1/3-x,2/3-y,2/3-z'
  '2/3-x,1/3-y,1/3-z'
  '1/3+y,2/3-x+y,2/3-z'
  '2/3+y,1/3-x+y,1/3-z'
  '1/3+x-y,2/3+x,2/3-z'
  '2/3+x-y,1/3+x,1/3-z'
  '1/3+y,2/3+x,1/6-z'
  '2/3+y,1/3+x,5/6-z'
  '1/3-x,2/3-x+y,1/6-z'
  '2/3-x,1/3-x+y,5/6-z'
  '1/3+x-y,2/3-y,1/6-z'
  '2/3+x-y,1/3-y,5/6-z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Cr3+   3.000
  P5+    5.000
  O2-   -2.000
  Na1+   1.000
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Cr1   Cr3+  12 c 0. 0. 0.1465(4) 1.  0 d
  P1    P5+   18 e 0.2911(5) 0. 0.25 1.  0 d
  O1    O2-   36 f 0.1746(5) -0.0306(5) 0.1934(2) 1.  0 d
  O2    O2-   36 f 0.1925(4) 0.1675(5) 0.0899(1) 1.  0 d
  Na1   Na1+   6 b 0. 0. 0. 0.79(4)  0 d
  Na2   Na1+  18 e 0.6315(14) 0. 0.25 0.73(4)  0 d
loop_
_atom_site_aniso_label
_atom_site_aniso_B_11
_atom_site_aniso_B_12
_atom_site_aniso_B_13
_atom_site_aniso_B_22
_atom_site_aniso_B_23
_atom_site_aniso_B_33
  Na1   16.9(2) 8.45 0. 16.9 0. 2.6(1)
  Na2   1.9(5) 1.3 0.73 2.6(6) 1.45 8.7(9)