The material structure described by Ba3Si6O9N4 crystallizes in the trigonal P3 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to one N(1), three equivalent O(2), and three equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent N(2), one O(1), and one O(3) atom to form corner-sharing SiN2O2 tetrahedra. In the second Si site, Si(2) is bonded to one N(1), one N(2), one O(1), and one O(2) atom to form corner-sharing SiN2O2 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to one Ba(2) and three equivalent Si(2) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Si(2) and two equivalent Si(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one Si(1) atom. is represented by the CIF file [CIF]
data_Ba3Si6N4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.324
_cell_length_b   7.324
_cell_length_c   6.885
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   319.819
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ba  Ba0  1  0.333  0.667  0.686  1.0
  Ba  Ba1  1  0.000  0.000  0.560  1.0
  Ba  Ba2  1  0.667  0.333  0.748  1.0
  Si  Si3  1  0.451  0.074  0.256  1.0
  Si  Si4  1  0.040  0.787  0.045  1.0
  Si  Si5  1  0.213  0.253  0.045  1.0
  Si  Si6  1  0.747  0.960  0.045  1.0
  Si  Si7  1  0.624  0.549  0.256  1.0
  Si  Si8  1  0.926  0.376  0.256  1.0
  N  N9  1  0.000  0.000  0.094  1.0
  N  N10  1  0.869  0.575  0.192  1.0
  N  N11  1  0.425  0.295  0.192  1.0
  N  N12  1  0.705  0.131  0.192  1.0
  O  O13  1  0.292  0.882  0.105  1.0
  O  O14  1  0.590  0.708  0.105  1.0
  O  O15  1  0.010  0.720  0.818  1.0
  O  O16  1  0.280  0.289  0.818  1.0
  O  O17  1  0.624  0.608  0.482  1.0
  O  O18  1  0.711  0.990  0.818  1.0
  O  O19  1  0.392  0.016  0.482  1.0
  O  O20  1  0.984  0.376  0.482  1.0
  O  O21  1  0.118  0.410  0.105  1.0
[/CIF]
.
The material structure described by Ba3Si6O9N4 crystallizes in the trigonal P3 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to one N(1), three equivalent O(2), and three equivalent O(3) atoms. In the third Ba site, Ba(3) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(3) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent N(2), one O(1), and one O(3) atom to form corner-sharing SiN2O2 tetrahedra. In the second Si site, Si(2) is bonded to one N(1), one N(2), one O(1), and one O(2) atom to form corner-sharing SiN2O2 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal planar geometry to one Ba(2) and three equivalent Si(2) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Si(2) and two equivalent Si(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Si(1) and one Si(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(3), and one Si(1) atom. is represented by the CIF file [CIF]
data_Ba3Si6N4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.324
_cell_length_b   7.324
_cell_length_c   6.885
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   319.819
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ba  Ba0  1  0.333  0.667  0.686  1.0
  Ba  Ba1  1  0.000  0.000  0.560  1.0
  Ba  Ba2  1  0.667  0.333  0.748  1.0
  Si  Si3  1  0.451  0.074  0.256  1.0
  Si  Si4  1  0.040  0.787  0.045  1.0
  Si  Si5  1  0.213  0.253  0.045  1.0
  Si  Si6  1  0.747  0.960  0.045  1.0
  Si  Si7  1  0.624  0.549  0.256  1.0
  Si  Si8  1  0.926  0.376  0.256  1.0
  N  N9  1  0.000  0.000  0.094  1.0
  N  N10  1  0.869  0.575  0.192  1.0
  N  N11  1  0.425  0.295  0.192  1.0
  N  N12  1  0.705  0.131  0.192  1.0
  O  O13  1  0.292  0.882  0.105  1.0
  O  O14  1  0.590  0.708  0.105  1.0
  O  O15  1  0.010  0.720  0.818  1.0
  O  O16  1  0.280  0.289  0.818  1.0
  O  O17  1  0.624  0.608  0.482  1.0
  O  O18  1  0.711  0.990  0.818  1.0
  O  O19  1  0.392  0.016  0.482  1.0
  O  O20  1  0.984  0.376  0.482  1.0
  O  O21  1  0.118  0.410  0.105  1.0
[/CIF]
.