data_1011252
_chemical_name_systematic          'Calcium zinc silicate *'
_chemical_name_mineral             'Hardystonite'
_chemical_compound_source          'from Franklin, New Jersey'
_chemical_formula_structural       'Ca2 Zn Si2 O7'
_chemical_formula_sum              'Ca2 O7 Si2 Zn'
_publ_section_title                'The Structure of Hardystonite Ca2 Zn Si2 O7'
loop_
_publ_author_name
  'Warren, B E'
  'Trautz, O R'
_journal_name_full
;
Zeitschrift fuer Kristallographie, Kristallgeometrie, Kristallphysik,
Kristallchemie (-144,1977)
;
_journal_coden_ASTM                ZEKGAX
_journal_volume                    75
_journal_year                      1930
_journal_page_first                525
_journal_page_last                 528
_cell_length_a                     7.846
_cell_length_b                     7.846
_cell_length_c                     5.
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       307.8
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P -4 21 m'
_symmetry_Int_Tables_number        113
_symmetry_cell_setting             tetragonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2-x,1/2+y,-z'
  '-x,-y,z'
  '1/2+x,1/2-y,-z'
  '-y,x,-z'
  '1/2+y,1/2+x,z'
  'y,-x,-z'
  '1/2-y,1/2-x,z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Ca2+   2.000
  Si4+   4.000
  Zn2+   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+   4 e 0.33 0.17 -0.49 1.  0 d
  Si1   Si4+   4 e 0.14 0.36 -0.05 1.  0 d
  Zn1   Zn2+   2 a 0. 0. 0. 1.  0 d
  O1    O2-    2 c 0.5 0. 0.19 1.  0 d
  O2    O2-    4 e 0.14 0.36 0.26 1.  0 d
  O3    O2-    8 f 0.08 0.18 -0.19 1.  0 d