The compound described by Li2Sr4Ta2Al2N8O crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded in a 2-coordinate geometry to one N(3) and one O(1) atom. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), two equivalent N(2), and one O(1) atom. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one N(3), two equivalent N(1), two equivalent N(2), two equivalent N(4), and one O(1) atom. Ta(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form TaN4 tetrahedra that share corners with four equivalent Al(1)N4 tetrahedra. Al(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form AlN4 tetrahedra that share corners with four equivalent Ta(1)N4 tetrahedra. There are four inequivalent N sites. In the first N site, N(4) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ta(1), and one Al(1) atom. In the second N site, N(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ta(1), and one Al(1) atom. In the third N site, N(2) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Al(1) atom. In the fourth N site, N(3) is bonded in a 3-coordinate geometry to one Li(1), one Sr(1), one Sr(2), one Ta(1), and one Al(1) atom. O(1) is bonded in a distorted octahedral geometry to two equivalent Li(1), two equivalent Sr(1), and two equivalent Sr(2) atoms. is represented by the CIF card [CIF]
data_Sr4Li2Ta2Al2N8O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.090
_cell_length_b   6.052
_cell_length_c   10.964
_cell_angle_alpha   59.865
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   579.016
_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
  Sr  Sr0  1  0.760  0.433  0.069  1.0
  Sr  Sr1  1  0.740  0.433  0.569  1.0
  Sr  Sr2  1  0.240  0.567  0.931  1.0
  Sr  Sr3  1  0.260  0.567  0.431  1.0
  Sr  Sr4  1  0.935  0.768  0.697  1.0
  Sr  Sr5  1  0.565  0.768  0.197  1.0
  Sr  Sr6  1  0.065  0.232  0.303  1.0
  Sr  Sr7  1  0.435  0.232  0.803  1.0
  Li  Li8  1  0.007  0.810  0.997  1.0
  Li  Li9  1  0.493  0.810  0.497  1.0
  Li  Li10  1  0.993  0.190  0.003  1.0
  Li  Li11  1  0.507  0.190  0.503  1.0
  Ta  Ta12  1  0.598  0.773  0.761  1.0
  Ta  Ta13  1  0.902  0.773  0.261  1.0
  Ta  Ta14  1  0.402  0.227  0.239  1.0
  Ta  Ta15  1  0.098  0.227  0.739  1.0
  Al  Al16  1  0.756  0.118  0.900  1.0
  Al  Al17  1  0.744  0.118  0.400  1.0
  Al  Al18  1  0.244  0.882  0.100  1.0
  Al  Al19  1  0.256  0.882  0.600  1.0
  N  N20  1  0.634  0.888  0.896  1.0
  N  N21  1  0.866  0.888  0.396  1.0
  N  N22  1  0.366  0.112  0.104  1.0
  N  N23  1  0.134  0.112  0.604  1.0
  N  N24  1  0.666  0.430  0.833  1.0
  N  N25  1  0.834  0.430  0.333  1.0
  N  N26  1  0.334  0.570  0.167  1.0
  N  N27  1  0.166  0.570  0.667  1.0
  N  N28  1  0.811  0.990  0.085  1.0
  N  N29  1  0.689  0.990  0.585  1.0
  N  N30  1  0.189  0.010  0.915  1.0
  N  N31  1  0.311  0.010  0.415  1.0
  N  N32  1  0.910  0.193  0.788  1.0
  N  N33  1  0.590  0.193  0.288  1.0
  N  N34  1  0.090  0.807  0.212  1.0
  N  N35  1  0.410  0.807  0.712  1.0
  O  O36  1  0.000  0.500  0.000  1.0
  O  O37  1  0.500  0.500  0.500  1.0
[/CIF]
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The compound described by Li2Sr4Ta2Al2N8O crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded in a 2-coordinate geometry to one N(3) and one O(1) atom. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), two equivalent N(2), and one O(1) atom. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one N(3), two equivalent N(1), two equivalent N(2), two equivalent N(4), and one O(1) atom. Ta(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form TaN4 tetrahedra that share corners with four equivalent Al(1)N4 tetrahedra. Al(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form AlN4 tetrahedra that share corners with four equivalent Ta(1)N4 tetrahedra. There are four inequivalent N sites. In the first N site, N(4) is bonded in a 2-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ta(1), and one Al(1) atom. In the second N site, N(1) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ta(1), and one Al(1) atom. In the third N site, N(2) is bonded in a 2-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Ta(1), and one Al(1) atom. In the fourth N site, N(3) is bonded in a 3-coordinate geometry to one Li(1), one Sr(1), one Sr(2), one Ta(1), and one Al(1) atom. O(1) is bonded in a distorted octahedral geometry to two equivalent Li(1), two equivalent Sr(1), and two equivalent Sr(2) atoms. is represented by the CIF card [CIF]
data_Sr4Li2Ta2Al2N8O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.090
_cell_length_b   6.052
_cell_length_c   10.964
_cell_angle_alpha   59.865
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   579.016
_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
  Sr  Sr0  1  0.760  0.433  0.069  1.0
  Sr  Sr1  1  0.740  0.433  0.569  1.0
  Sr  Sr2  1  0.240  0.567  0.931  1.0
  Sr  Sr3  1  0.260  0.567  0.431  1.0
  Sr  Sr4  1  0.935  0.768  0.697  1.0
  Sr  Sr5  1  0.565  0.768  0.197  1.0
  Sr  Sr6  1  0.065  0.232  0.303  1.0
  Sr  Sr7  1  0.435  0.232  0.803  1.0
  Li  Li8  1  0.007  0.810  0.997  1.0
  Li  Li9  1  0.493  0.810  0.497  1.0
  Li  Li10  1  0.993  0.190  0.003  1.0
  Li  Li11  1  0.507  0.190  0.503  1.0
  Ta  Ta12  1  0.598  0.773  0.761  1.0
  Ta  Ta13  1  0.902  0.773  0.261  1.0
  Ta  Ta14  1  0.402  0.227  0.239  1.0
  Ta  Ta15  1  0.098  0.227  0.739  1.0
  Al  Al16  1  0.756  0.118  0.900  1.0
  Al  Al17  1  0.744  0.118  0.400  1.0
  Al  Al18  1  0.244  0.882  0.100  1.0
  Al  Al19  1  0.256  0.882  0.600  1.0
  N  N20  1  0.634  0.888  0.896  1.0
  N  N21  1  0.866  0.888  0.396  1.0
  N  N22  1  0.366  0.112  0.104  1.0
  N  N23  1  0.134  0.112  0.604  1.0
  N  N24  1  0.666  0.430  0.833  1.0
  N  N25  1  0.834  0.430  0.333  1.0
  N  N26  1  0.334  0.570  0.167  1.0
  N  N27  1  0.166  0.570  0.667  1.0
  N  N28  1  0.811  0.990  0.085  1.0
  N  N29  1  0.689  0.990  0.585  1.0
  N  N30  1  0.189  0.010  0.915  1.0
  N  N31  1  0.311  0.010  0.415  1.0
  N  N32  1  0.910  0.193  0.788  1.0
  N  N33  1  0.590  0.193  0.288  1.0
  N  N34  1  0.090  0.807  0.212  1.0
  N  N35  1  0.410  0.807  0.712  1.0
  O  O36  1  0.000  0.500  0.000  1.0
  O  O37  1  0.500  0.500  0.500  1.0
[/CIF]
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