The material described by BaAl2Si3O4N4 crystallizes in the orthorhombic Cmc2_1 space group. Ba(1) is bonded in a 11-coordinate geometry to one N(1), two equivalent N(3), two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share  a cornercorner with one Al(2)N3O tetrahedra,  a cornercorner with one Si(1)N3O tetrahedra, and corners with two equivalent Si(2)N3O tetrahedra. In the second Al site, Al(2) is bonded to one N(2), two equivalent N(3), and one O(3) atom to form AlN3O tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Si(1)N3O tetrahedra, and corners with four equivalent Si(2)N3O tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), two equivalent N(3), and one O(2) atom to form SiN3O tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Al(2)N3O tetrahedra, and corners with four equivalent Si(2)N3O tetrahedra. In the second Si site, Si(2) is bonded to one N(1), one N(2), one N(3), and one O(1) atom to form SiN3O tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Al(2)N3O tetrahedra, corners with two equivalent Si(1)N3O tetrahedra, and corners with two equivalent Si(2)N3O tetrahedra. There are three inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Ba(1), one Si(1), and two equivalent Si(2) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Al(2) and two equivalent Si(2) atoms. In the third N site, N(3) is bonded in a trigonal planar geometry to one Ba(1), one Al(2), one Si(1), and one Si(2) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one Al(1), and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Ba(1), one Al(1), and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Ba(1), one Al(1), and one Al(2) atom. is represented by the CIF file [CIF]
data_BaAl2Si3(NO)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.418
_cell_length_b   7.418
_cell_length_c   9.579
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   134.175
_symmetry_Int_Tables_number   1
_cell_volume   378.062
_cell_formula_units_Z   2
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  0.983  0.017  0.001  1.0
  Ba  Ba1  1  0.017  0.983  0.501  1.0
  Al  Al2  1  0.473  0.527  0.755  1.0
  Al  Al3  1  0.527  0.473  0.255  1.0
  Al  Al4  1  0.287  0.713  0.539  1.0
  Al  Al5  1  0.713  0.287  0.039  1.0
  Si  Si6  1  0.298  0.702  0.986  1.0
  Si  Si7  1  0.702  0.298  0.486  1.0
  Si  Si8  1  0.429  0.083  0.761  1.0
  Si  Si9  1  0.917  0.571  0.761  1.0
  Si  Si10  1  0.571  0.917  0.261  1.0
  Si  Si11  1  0.083  0.429  0.261  1.0
  N  N12  1  0.208  0.792  0.851  1.0
  N  N13  1  0.792  0.208  0.351  1.0
  N  N14  1  0.712  0.288  0.846  1.0
  N  N15  1  0.288  0.712  0.346  1.0
  N  N16  1  0.465  0.043  0.589  1.0
  N  N17  1  0.957  0.535  0.589  1.0
  N  N18  1  0.535  0.957  0.089  1.0
  N  N19  1  0.043  0.465  0.089  1.0
  O  O20  1  0.299  0.199  0.759  1.0
  O  O21  1  0.801  0.701  0.759  1.0
  O  O22  1  0.701  0.801  0.259  1.0
  O  O23  1  0.199  0.299  0.259  1.0
  O  O24  1  0.406  0.594  0.911  1.0
  O  O25  1  0.594  0.406  0.411  1.0
  O  O26  1  0.406  0.594  0.603  1.0
  O  O27  1  0.594  0.406  0.103  1.0
[/CIF]
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The material described by BaAl2Si3O4N4 crystallizes in the orthorhombic Cmc2_1 space group. Ba(1) is bonded in a 11-coordinate geometry to one N(1), two equivalent N(3), two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form AlO4 tetrahedra that share  a cornercorner with one Al(2)N3O tetrahedra,  a cornercorner with one Si(1)N3O tetrahedra, and corners with two equivalent Si(2)N3O tetrahedra. In the second Al site, Al(2) is bonded to one N(2), two equivalent N(3), and one O(3) atom to form AlN3O tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Si(1)N3O tetrahedra, and corners with four equivalent Si(2)N3O tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), two equivalent N(3), and one O(2) atom to form SiN3O tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Al(2)N3O tetrahedra, and corners with four equivalent Si(2)N3O tetrahedra. In the second Si site, Si(2) is bonded to one N(1), one N(2), one N(3), and one O(1) atom to form SiN3O tetrahedra that share  a cornercorner with one Al(1)O4 tetrahedra, corners with two equivalent Al(2)N3O tetrahedra, corners with two equivalent Si(1)N3O tetrahedra, and corners with two equivalent Si(2)N3O tetrahedra. There are three inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Ba(1), one Si(1), and two equivalent Si(2) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Al(2) and two equivalent Si(2) atoms. In the third N site, N(3) is bonded in a trigonal planar geometry to one Ba(1), one Al(2), one Si(1), and one Si(2) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Ba(1), one Al(1), and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Ba(1), one Al(1), and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to two equivalent Ba(1), one Al(1), and one Al(2) atom. is represented by the CIF file [CIF]
data_BaAl2Si3(NO)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.418
_cell_length_b   7.418
_cell_length_c   9.579
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   134.175
_symmetry_Int_Tables_number   1
_cell_volume   378.062
_cell_formula_units_Z   2
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  0.983  0.017  0.001  1.0
  Ba  Ba1  1  0.017  0.983  0.501  1.0
  Al  Al2  1  0.473  0.527  0.755  1.0
  Al  Al3  1  0.527  0.473  0.255  1.0
  Al  Al4  1  0.287  0.713  0.539  1.0
  Al  Al5  1  0.713  0.287  0.039  1.0
  Si  Si6  1  0.298  0.702  0.986  1.0
  Si  Si7  1  0.702  0.298  0.486  1.0
  Si  Si8  1  0.429  0.083  0.761  1.0
  Si  Si9  1  0.917  0.571  0.761  1.0
  Si  Si10  1  0.571  0.917  0.261  1.0
  Si  Si11  1  0.083  0.429  0.261  1.0
  N  N12  1  0.208  0.792  0.851  1.0
  N  N13  1  0.792  0.208  0.351  1.0
  N  N14  1  0.712  0.288  0.846  1.0
  N  N15  1  0.288  0.712  0.346  1.0
  N  N16  1  0.465  0.043  0.589  1.0
  N  N17  1  0.957  0.535  0.589  1.0
  N  N18  1  0.535  0.957  0.089  1.0
  N  N19  1  0.043  0.465  0.089  1.0
  O  O20  1  0.299  0.199  0.759  1.0
  O  O21  1  0.801  0.701  0.759  1.0
  O  O22  1  0.701  0.801  0.259  1.0
  O  O23  1  0.199  0.299  0.259  1.0
  O  O24  1  0.406  0.594  0.911  1.0
  O  O25  1  0.594  0.406  0.411  1.0
  O  O26  1  0.406  0.594  0.603  1.0
  O  O27  1  0.594  0.406  0.103  1.0
[/CIF]
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