data_1007234
_chemical_name_systematic          'Barium titanium silicate'
_chemical_name_mineral             'Fresnoite'
_chemical_compound_source          'synthetic at 1350 C'
_chemical_formula_structural       'Ba2 Ti Si2 O8'
_chemical_formula_sum              'Ba2 O8 Si2 Ti'
_publ_section_title                'Structure cristalline de la fresnoite'
loop_
_publ_author_name
  'Masse, R'
  'Grenier, J C'
  'Durif, A'
_journal_name_full
;
Bulletin de la Societe Francaise de Mineralogie et de Cristallographie
(72,1949-100,1977)
;
_journal_coden_ASTM                BUFCAE
_journal_volume                    90
_journal_year                      1967
_journal_page_first                20
_journal_page_last                 23
_cell_length_a                     8.52
_cell_length_b                     8.52
_cell_length_c                     5.21
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       378.2
_cell_formula_units_Z              2
_symmetry_space_group_name_H-M     'P 4 b m'
_symmetry_Int_Tables_number        100
_symmetry_cell_setting             tetragonal
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '-x,-y,z'
  '1/2+x,1/2-y,z'
  '1/2-x,1/2+y,z'
  '-y,x,z'
  'y,-x,z'
  '1/2+y,1/2+x,z'
  '1/2-y,1/2-x,z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Ba2+   2.000
  Ti4+   4.000
  Si4+   4.000
  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
  Ba1   Ba2+   4 c 0.173 0.673 0. 1.  0 d
  Ti1   Ti4+   2 a 0. 0. 0.54 1.  0 d
  Si1   Si4+   4 c 0.63 0.13 0.52 1.  0 d
  O1    O2-    8 d 0.09 0.206 0.655 1.  0 d
  O2    O2-    4 c 0.618 0.118 0.21 1.  0 d
  O3    O2-    2 b 0.5 0. 0.62 1.  0 d
  O4    O2-    2 a 0. 0. 0.16 1.  0 d
_refine_ls_R_factor_all            0.12