data_2002181
_chemical_name_systematic          'Calcium holmium oxide (1/1/2.5)'
_chemical_formula_structural       'Ca Ho O2.5'
_chemical_formula_sum              'Ca Ho O2.5'
_publ_section_title
;
Ein Beitrag zur Kristallchemie dreiwertiger Seltenerdoxide. Zur
Stabilisierung der monoklinen b-Form
;
loop_
_publ_author_name
  'Muschick, W'
  'Mueller-Buschbaum, Hk'
_journal_name_full
;
Zeitschrift fuer Naturforschung, Teil B. Anorganische Chemie,
Organische Chemie (2,1947-32,1977)
;
_journal_volume                    32
_journal_year                      1977
_journal_page_first                495
_journal_page_last                 498
_cell_length_a                     6.566
_cell_length_b                     3.567
_cell_length_c                     5.894
_cell_angle_alpha                  90
_cell_angle_beta                   92.3
_cell_angle_gamma                  90
_cell_volume                       137.9
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P 1 21/m 1'
_symmetry_Int_Tables_number        11
_symmetry_cell_setting             monoclinic
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,1/2+y,-z'
  '-x,-y,-z'
  'x,1/2-y,z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Ca2+   2.000
  Ho3+   3.000
  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 e 0.431 0.25 0.2451 0.5  0 d
  Ca2   Ca2+   2 e 0.1193 0.25 0.7722 0.5  0 d
  Ho1   Ho3+   2 e 0.431 0.25 0.2451 0.5  0 d
  Ho2   Ho3+   2 e 0.1193 0.25 0.7722 0.5  0 d
  O1    O2-    2 e 0.686 0.25 0.013 0.8333  0 d
  O2    O2-    2 e 0.089 0.25 0.209 0.8333  0 d
  O3    O2-    2 e 0.416 0.25 0.608 0.8333  0 d
_refine_ls_R_factor_all            0.099