data_9006345
_publ_section_title
;
 Soidium trisilicate: A new high-pressure silicate structure (Na2Si[Si2O7])
;
_journal_name_full               'Physics and Chemistry of Minerals'
_journal_page_first              383
_journal_page_last               386
_journal_volume                  22
_journal_year                    1995
_chemical_formula_structural     Na2SiSi2O7
_chemical_formula_sum            'Na2 O7 Si3'
_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                 102.64
_cell_angle_gamma                90
_cell_length_a                   8.922
_cell_length_b                   4.8490
_cell_length_c                   11.567
_cell_volume                     488.292
_exptl_crystal_density_diffrn    3.295
_[local]_cod_chemical_formula_sum_orig 'Si3 Na2 O7'
_cod_database_code               9006345
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
Si1 0.45777 0.28452 0.11515
Si2 0.25000 0.25000 0.50000
Na 0.14770 0.29478 0.18326
O1 0.36080 0.56388 0.12681
O2 0.36502 0.04726 0.03572
O3 0.37597 0.36728 0.41000
O4 0.00000 0.64740 0.25000
