data_9000194
_publ_section_title
;The crystal structure of SnTa2O7, thoreaulite, an example of tin in five-fold
 coordination
;
_journal_name_full               'American Mineralogist'
_journal_page_first              367
_journal_page_last               377
_journal_volume                  55
_journal_year                    1970
_chemical_formula_sum            'O7 Sn Ta2'
_chemical_name_mineral           Thoreaulite
_space_group_IT_number           15
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_cell_angle_alpha                90
_cell_angle_beta                 91.0
_cell_angle_gamma                90
_cell_length_a                   17.140
_cell_length_b                   4.865
_cell_length_c                   5.548
_cell_volume                     462.556
_exptl_crystal_density_diffrn    8.510
_[local]_cod_chemical_formula_sum_orig 'Sn Ta2 O7'
_cod_database_code               9000194
loop_
_symmetry_equiv_pos_as_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
-x,y,1/2-z
1/2-x,1/2+y,1/2-z
-x,-y,-z
1/2-x,1/2-y,-z
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
Sn 0.00000 0.23000 0.25000 0.01520
Ta 0.16980 0.24030 0.66750 0.01140
O1 0.00000 0.39200 0.75000 0.04559
O2 0.07500 0.09700 0.59900 0.03293
O3 0.12400 0.56700 0.42700 0.04559
O4 0.21700 0.07700 0.34200 0.04433
