# CIF file
data_findsym-output
_audit_creation_method FINDSYM

_chemical_name_mineral 'alpha-Si3N4'
_chemical_formula_sum 'N4 Si3'

loop_
_publ_author_name
 'D. Hardie'
 'K. H. Jack'
_journal_name_full_name
;
 Nature
;
_journal_volume 180
_journal_year 1957
_journal_page_first 332
_journal_page_last 333
_publ_Section_title
;
 Crystal structures of silicon nitride
;

# Found in Pearson's Crystal Data - Crystal Structure Database for Inorganic Compounds, 2013

_aflow_title 'Nierite ($\alpha$-Si$_{3}$N$_{4}$) Structure'
_aflow_proto 'A4B3_hP28_159_ab2c_2c'
_aflow_params 'a,c/a,z_{1},z_{2},x_{3},y_{3},z_{3},x_{4},y_{4},z_{4},x_{5},y_{5},z_{5},x_{6},y_{6},z_{6}'
_aflow_params_values '7.7479899913,0.724961280333,0.0,0.3649,0.0424,0.3891,0.0408,0.3169,0.3198,0.2712,0.0821,0.5089,0.3172,0.1712,0.2563,0.0274'
_aflow_Strukturbericht 'None'
_aflow_Pearson 'hP28'

_cell_length_a    7.7479899913
_cell_length_b    7.7479899913
_cell_length_c    5.6169927441
_cell_angle_alpha 90.0000000000
_cell_angle_beta  90.0000000000
_cell_angle_gamma 120.0000000000
 
_symmetry_space_group_name_H-M "P 3 1 c"
_symmetry_Int_Tables_number 159
 
loop_
_space_group_symop_id
_space_group_symop_operation_xyz
1 x,y,z
2 -y,x-y,z
3 -x+y,-x,z
4 -x,-x+y,z+1/2
5 x-y,-y,z+1/2
6 y,x,z+1/2
 
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
N1  N    2 a 0.00000 0.00000 0.00000 1.00000
N2  N    2 b 0.33333 0.66667 0.36490 1.00000
N3  N    6 c 0.04240 0.38910 0.04080 1.00000
N4  N    6 c 0.31690 0.31980 0.27120 1.00000
Si1 Si   6 c 0.08210 0.50890 0.31720 1.00000
Si2 Si   6 c 0.17120 0.25630 0.02740 1.00000
