The compound described by SrSiAl2O3N2 crystallizes in the orthorhombic P2_12_12_1 space group. Sr(1) is bonded in a 9-coordinate geometry to one N(1), two equivalent N(2), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one N(2), one O(1), one O(2), and one O(3) atom to form AlNO3 tetrahedra that share corners with two equivalent Si(1)N3O tetrahedra and corners with three equivalent Al(2)N2O2 tetrahedra. In the second Al site, Al(2) is bonded to one N(1), one N(2), one O(1), and one O(3) atom to form AlN2O2 tetrahedra that share corners with three equivalent Al(1)NO3 tetrahedra and corners with three equivalent Si(1)N3O tetrahedra. Si(1) is bonded to one N(2), two equivalent N(1), and one O(2) atom to form SiN3O tetrahedra that share corners with two equivalent Al(1)NO3 tetrahedra, corners with two equivalent Si(1)N3O tetrahedra, and corners with three equivalent Al(2)N2O2 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 3-coordinate geometry to one Sr(1), one Al(2), and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to two equivalent Sr(1), one Al(1), one Al(2), and one Si(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), one Al(1), and one Al(2) atom to form distorted corner-sharing OSr2Al2 tetrahedra. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Sr(1), one Al(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(1), one Al(1), and one Al(2) atom. is represented by the CIF file [CIF]
data_SrAl2SiN2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.980
_cell_length_b   8.129
_cell_length_c   11.433
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   462.778
_cell_formula_units_Z   4
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
  Sr  Sr0  1  0.511  0.041  0.162  1.0
  Sr  Sr1  1  0.011  0.459  0.838  1.0
  Sr  Sr2  1  0.989  0.959  0.662  1.0
  Sr  Sr3  1  0.489  0.541  0.338  1.0
  Al  Al4  1  0.500  0.664  0.661  1.0
  Al  Al5  1  1.000  0.836  0.339  1.0
  Al  Al6  1  0.989  0.528  0.543  1.0
  Al  Al7  1  0.500  0.164  0.839  1.0
  Al  Al8  1  0.000  0.336  0.161  1.0
  Al  Al9  1  0.489  0.972  0.457  1.0
  Al  Al10  1  0.511  0.472  0.043  1.0
  Al  Al11  1  0.011  0.028  0.957  1.0
  Si  Si12  1  0.994  0.702  0.075  1.0
  Si  Si13  1  0.506  0.298  0.575  1.0
  Si  Si14  1  0.494  0.798  0.925  1.0
  Si  Si15  1  0.006  0.202  0.425  1.0
  N  N16  1  0.294  0.157  0.507  1.0
  N  N17  1  0.206  0.843  0.007  1.0
  N  N18  1  0.335  0.482  0.594  1.0
  N  N19  1  0.706  0.657  0.993  1.0
  N  N20  1  0.835  0.018  0.406  1.0
  N  N21  1  0.165  0.518  0.094  1.0
  N  N22  1  0.794  0.343  0.493  1.0
  N  N23  1  0.665  0.982  0.906  1.0
  O  O24  1  0.649  0.369  0.168  1.0
  O  O25  1  0.149  0.131  0.832  1.0
  O  O26  1  0.351  0.869  0.332  1.0
  O  O27  1  0.125  0.291  0.304  1.0
  O  O28  1  0.875  0.791  0.196  1.0
  O  O29  1  0.044  0.152  0.083  1.0
  O  O30  1  0.544  0.348  0.917  1.0
  O  O31  1  0.375  0.709  0.804  1.0
  O  O32  1  0.956  0.652  0.417  1.0
  O  O33  1  0.851  0.631  0.668  1.0
  O  O34  1  0.456  0.848  0.583  1.0
  O  O35  1  0.625  0.209  0.696  1.0
[/CIF]
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The compound described by SrSiAl2O3N2 crystallizes in the orthorhombic P2_12_12_1 space group. Sr(1) is bonded in a 9-coordinate geometry to one N(1), two equivalent N(2), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one N(2), one O(1), one O(2), and one O(3) atom to form AlNO3 tetrahedra that share corners with two equivalent Si(1)N3O tetrahedra and corners with three equivalent Al(2)N2O2 tetrahedra. In the second Al site, Al(2) is bonded to one N(1), one N(2), one O(1), and one O(3) atom to form AlN2O2 tetrahedra that share corners with three equivalent Al(1)NO3 tetrahedra and corners with three equivalent Si(1)N3O tetrahedra. Si(1) is bonded to one N(2), two equivalent N(1), and one O(2) atom to form SiN3O tetrahedra that share corners with two equivalent Al(1)NO3 tetrahedra, corners with two equivalent Si(1)N3O tetrahedra, and corners with three equivalent Al(2)N2O2 tetrahedra. There are two inequivalent N sites. In the first N site, N(1) is bonded in a 3-coordinate geometry to one Sr(1), one Al(2), and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a distorted trigonal planar geometry to two equivalent Sr(1), one Al(1), one Al(2), and one Si(1) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), one Al(1), and one Al(2) atom to form distorted corner-sharing OSr2Al2 tetrahedra. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Sr(1), one Al(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(1), one Al(1), and one Al(2) atom. is represented by the CIF file [CIF]
data_SrAl2SiN2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.980
_cell_length_b   8.129
_cell_length_c   11.433
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   462.778
_cell_formula_units_Z   4
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
  Sr  Sr0  1  0.511  0.041  0.162  1.0
  Sr  Sr1  1  0.011  0.459  0.838  1.0
  Sr  Sr2  1  0.989  0.959  0.662  1.0
  Sr  Sr3  1  0.489  0.541  0.338  1.0
  Al  Al4  1  0.500  0.664  0.661  1.0
  Al  Al5  1  1.000  0.836  0.339  1.0
  Al  Al6  1  0.989  0.528  0.543  1.0
  Al  Al7  1  0.500  0.164  0.839  1.0
  Al  Al8  1  0.000  0.336  0.161  1.0
  Al  Al9  1  0.489  0.972  0.457  1.0
  Al  Al10  1  0.511  0.472  0.043  1.0
  Al  Al11  1  0.011  0.028  0.957  1.0
  Si  Si12  1  0.994  0.702  0.075  1.0
  Si  Si13  1  0.506  0.298  0.575  1.0
  Si  Si14  1  0.494  0.798  0.925  1.0
  Si  Si15  1  0.006  0.202  0.425  1.0
  N  N16  1  0.294  0.157  0.507  1.0
  N  N17  1  0.206  0.843  0.007  1.0
  N  N18  1  0.335  0.482  0.594  1.0
  N  N19  1  0.706  0.657  0.993  1.0
  N  N20  1  0.835  0.018  0.406  1.0
  N  N21  1  0.165  0.518  0.094  1.0
  N  N22  1  0.794  0.343  0.493  1.0
  N  N23  1  0.665  0.982  0.906  1.0
  O  O24  1  0.649  0.369  0.168  1.0
  O  O25  1  0.149  0.131  0.832  1.0
  O  O26  1  0.351  0.869  0.332  1.0
  O  O27  1  0.125  0.291  0.304  1.0
  O  O28  1  0.875  0.791  0.196  1.0
  O  O29  1  0.044  0.152  0.083  1.0
  O  O30  1  0.544  0.348  0.917  1.0
  O  O31  1  0.375  0.709  0.804  1.0
  O  O32  1  0.956  0.652  0.417  1.0
  O  O33  1  0.851  0.631  0.668  1.0
  O  O34  1  0.456  0.848  0.583  1.0
  O  O35  1  0.625  0.209  0.696  1.0
[/CIF]
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