data_1100026
_chemical_name_systematic          'Strontium peroxide'
_chemical_formula_structural       'Sr O2'
_chemical_formula_sum              'O2 Sr'
_publ_section_title
;
The Structure of Strontium and Barium Peroxides, Sr O~2~ and Ba O~2~
;
loop_
_publ_author_name
  'Bernal, J D'
  'Djatlowa, E'
  'Kasarnowsky, I'
  'Reichstein, S'
  'Ward, A G'
_journal_name_full
;
Zeitschrift fuer Kristallographie, Kristallgeometrie, Kristallphysik,
Kristallchemie (-144,1977)
;
_journal_volume                    92
_journal_year                      1935
_journal_page_first                344
_journal_page_last                 354
_cell_length_a                     3.55
_cell_length_b                     3.55
_cell_length_c                     6.55
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       82.5
_cell_formula_units_Z              2
_exptl_crystal_density_meas        4.45
_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
  Sr2+   2.000
  O1-   -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
  Sr1   Sr2+   2 a 0. 0. 0. 1.  0 d
  O1    O1-    4 e 0. 0. 0.397 1.  0 d