data_1006108
_chemical_name_systematic          'Lanthanum calcium copper oxide (2/1/2/6.04)'
_chemical_formula_structural       '(La0.23 Ca0.77) (La1.77 Ca0.23) Cu2 O6.037'
_chemical_formula_sum              'Ca Cu2 La2 O6.037'
_publ_section_title
;
Oxygen excess and superconductivity at 45 K in La2 Ca Cu2 O6+y
;
loop_
_publ_author_name
  'Fuertes, A'
  'Obradors, X'
  'Navarro, J M'
  'Gomez-Romero, P'
  'Casan-Pastor, N'
  'Perez, F'
  'Fontcuberta, J'
  'Miravitlles, C'
  'Rodriguez-Carvajal, J'
  'Martinez, B'
_journal_name_full                 'Physica C (Amsterdam) (152,1988-)'
_journal_coden_ASTM                PHYCE6
_journal_volume                    170
_journal_year                      1990
_journal_page_first                153
_journal_page_last                 160
_cell_length_a                     3.83350(5)
_cell_length_b                     3.83350(5)
_cell_length_c                     19.51689(40)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       286.8
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'I 4/m m m'
_symmetry_Int_Tables_number        139
_symmetry_cell_setting             tetragonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,-y,z'
  '-x,y,z'
  'x,-y,z'
  '-y,x,z'
  'y,-x,z'
  'y,x,z'
  '-y,-x,z'
  '-x,-y,-z'
  'x,y,-z'
  'x,-y,-z'
  '-x,y,-z'
  'y,-x,-z'
  '-y,x,-z'
  '-y,-x,-z'
  'y,x,-z'
  '1/2+x,1/2+y,1/2+z'
  '1/2-x,1/2-y,1/2+z'
  '1/2-x,1/2+y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
  '1/2-y,1/2+x,1/2+z'
  '1/2+y,1/2-x,1/2+z'
  '1/2+y,1/2+x,1/2+z'
  '1/2-y,1/2-x,1/2+z'
  '1/2-x,1/2-y,1/2-z'
  '1/2+x,1/2+y,1/2-z'
  '1/2+x,1/2-y,1/2-z'
  '1/2-x,1/2+y,1/2-z'
  '1/2+y,1/2-x,1/2-z'
  '1/2-y,1/2+x,1/2-z'
  '1/2-y,1/2-x,1/2-z'
  '1/2+y,1/2+x,1/2-z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Ca2+   2.000
  La3+   3.000
  Cu2+   2.000
  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
  Ca1   Ca2+   2 a 0. 0. 0. 0.77(2)  0 d
  La1   La3+   2 a 0. 0. 0. 0.23(2)  0 d
  La2   La3+   4 e 0. 0. 0.1759(1) 0.885(2)  0 d
  Ca2   Ca2+   4 e 0. 0. 0.1759(1) 0.115(2)  0 d
  Cu1   Cu2+   4 e 0. 0. 0.5853(1) 1.  0 d
  O1    O2-    8 g 0. 0.5 0.0821(1) 1.  0 d
  O2    O2-    4 e 0. 0. 0.7039(1) 1.  0 d
  O3    O2-    2 b 0. 0. 0.5 0.037(8)  0 d
_refine_ls_R_factor_all            0.0651