data_global
_chemical_name_mineral 'Tilasite'
loop_
_publ_author_name
'Bladh K W'
'Corbett R K'
'McLean W J'
'Laughon R B'
_journal_name_full 'American Mineralogist'
_journal_volume 57 
_journal_year 1972
_journal_page_first 1880
_journal_page_last 1884
_publ_section_title
;
 The crystal structure of tilasite
;
_database_code_amcsd 0000298
_chemical_formula_sum 'As Ca Mg O4 F'
_cell_length_a 6.688
_cell_length_b 8.944
_cell_length_c 7.570
_cell_angle_alpha 90
_cell_angle_beta 121.17
_cell_angle_gamma 90
_cell_volume 387.447
_exptl_crystal_density_diffrn      3.811
_symmetry_space_group_name_H-M 'C 1 c 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,1/2+z'
  '1/2+x,1/2-y,1/2+z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
As   0.00000   0.42930   0.25000   0.00532
Ca   0.48670   0.58170   0.23920   0.00722
Mg   0.25200   0.74700   0.50000   0.00684
O1   0.01200   0.31100   0.07600   0.00887
O2   0.26300   0.96700   0.62600   0.00507
O3   0.24800   0.53700   0.38200   0.00887
O4   0.00100   0.31600   0.42200   0.00887
F   0.50800   0.33300   0.24700   0.00887