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#$Date: 2014-07-11 17:35:18 +0300 (Fri, 11 Jul 2014) $
#$Revision: 120071 $
#$URL: file:///home/coder/svn-repositories/cod/cif/1/00/12/1001218.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_1001218
_chemical_name_systematic          'Rubidium tricopper heptatantalum oxide'
_chemical_formula_structural       'Rb Cu3 Ta7 O21'
_chemical_formula_sum              'Cu3 O21 Rb Ta7'
_publ_section_title
;
Intergrowth of Hexagonal Tungsten Bronze and Perovskite-like
Structures: The Oxides A Cu~3~ M~7~ O~21~ (A = K, Rb, Cs, Tl; M = Nb,
Ta)
;
loop_
_publ_author_name
  'Benmoussa, A'
  'Groult, D'
  'Studer, F'
  'Raveau, B'
_journal_name_full                 'Journal of Solid State Chemistry'
_journal_coden_ASTM                JSSCBI
_journal_volume                    41
_journal_year                      1982
_journal_page_first                221
_journal_page_last                 226
_cell_length_a                     28.11(1)
_cell_length_b                     7.503(4)
_cell_length_c                     7.548(5)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       1591.9
_cell_formula_units_Z              4
_exptl_crystal_density_meas        7.86(5)
_symmetry_space_group_name_H-M     'C m m m'
_symmetry_Int_Tables_number        65
_symmetry_cell_setting             orthorhombic
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,-y,z'
  'x,-y,-z'
  '-x,y,-z'
  '-x,-y,-z'
  'x,y,-z'
  '-x,y,z'
  'x,-y,z'
  '1/2+x,1/2+y,z'
  '1/2-x,1/2-y,z'
  '1/2+x,1/2-y,-z'
  '1/2-x,1/2+y,-z'
  '1/2-x,1/2-y,-z'
  '1/2+x,1/2+y,-z'
  '1/2-x,1/2+y,z'
  '1/2+x,1/2-y,z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Rb1+   1.000
  Cu2+   2.000
  Ta5+   5.000
  O2-   -2.000
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
  Rb1   Rb1+   2 a 0. 0. 0. 1.  0 d
  Rb2   Rb1+   2 d 0. 0. 0.5 1.  0 d
  Cu1   Cu2+   4 h 0.173(3) 0. 0.5 1.  0 d
  Cu2   Cu2+   4 h 0.321(7) 0. 0.5 0.5  0 d
  Cu3   Cu2+   4 g 0.318(8) 0. 0. 1.  0 d
  Cu4   Cu2+   4 g 0.183(4) 0. 0. 0.5  0 d
  Ta1   Ta5+   4 l 0. 0.5 0.244(7) 1.  0 d
  Ta2   Ta5+  16 r 0.1131(8) 0.2477(16) 0.255(3) 1.  0 d
  Ta3   Ta5+   8 m 0.25 0.25 0.252(5) 1.  0 d
  O1    O2-    8 o 0.088(4) 0. 0.248(13) 1.  0 d
  O2    O2-    8 o 0.274(4) 0. 0.220(15) 1.  0 d
  O3    O2-    8 o 0.366(4) 0. 0.202(15) 1.  0 d
  O4    O2-   16 r 0.179(3) 0.164(5) 0.280(25) 1.  0 d
  O5    O2-   16 r 0.046(2) 0.304(8) 0.280(27) 1.  0 d
  O6    O2-    8 q 0.124(5) 0.322(12) 0.5 1.  0 d
  O7    O2-    8 p 0.128(5) 0.187(13) 0. 1.  0 d
  O8    O2-    8 q 0.236(9) 0.323(20) 0.5 0.5  0 d
  O9    O2-    8 p 0.238(9) 0.186(16) 0. 0.5  0 d
  O10   O2-    2 e 0.5 0. 0.5 1.  0 d
  O11   O2-    2 b 0.5 0. 0. 1.  0 d
_refine_ls_R_factor_all            0.08
_cod_database_code 1001218
_journal_paper_doi 10.1016/0022-4596(82)90205-5