The material structure described by Sr7Zr(Si2O7)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to one O(1), one O(3), and three equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded to six equivalent O(1) atoms to form SrO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Zr(1) is bonded to six equivalent O(3) atoms to form ZrO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Sr(2)O6 octahedra,  a cornercorner with one Zr(1)O6 octahedra, and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), and one Si(1) atom. In the second O site, O(2) is bonded to three equivalent Sr(1) and one Si(1) atom to form a mixture of distorted corner and edge-sharing OSr3Si tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Zr(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr7Zr(Si2O7)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.518
_cell_length_b   8.518
_cell_length_c   8.518
_cell_angle_alpha   106.067
_cell_angle_beta   106.067
_cell_angle_gamma   106.067
_symmetry_Int_Tables_number   1
_cell_volume   527.237
_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
  Sr  Sr0  1  0.152  0.628  0.751  1.0
  Sr  Sr1  1  0.249  0.848  0.372  1.0
  Sr  Sr2  1  0.500  0.500  0.500  1.0
  Sr  Sr3  1  0.848  0.372  0.249  1.0
  Sr  Sr4  1  0.751  0.152  0.628  1.0
  Sr  Sr5  1  0.372  0.249  0.848  1.0
  Sr  Sr6  1  0.628  0.751  0.152  1.0
  Zr  Zr7  1  0.000  0.000  0.000  1.0
  Si  Si8  1  0.542  0.927  0.817  1.0
  Si  Si9  1  0.817  0.542  0.927  1.0
  Si  Si10  1  0.073  0.183  0.458  1.0
  Si  Si11  1  0.183  0.458  0.073  1.0
  Si  Si12  1  0.927  0.817  0.542  1.0
  Si  Si13  1  0.458  0.073  0.183  1.0
  O  O14  1  0.715  0.745  0.455  1.0
  O  O15  1  0.458  0.012  0.681  1.0
  O  O16  1  0.242  0.983  0.125  1.0
  O  O17  1  0.983  0.125  0.242  1.0
  O  O18  1  0.455  0.715  0.745  1.0
  O  O19  1  0.681  0.458  0.012  1.0
  O  O20  1  0.545  0.285  0.255  1.0
  O  O21  1  0.745  0.455  0.715  1.0
  O  O22  1  0.988  0.319  0.542  1.0
  O  O23  1  0.758  0.017  0.875  1.0
  O  O24  1  0.012  0.681  0.458  1.0
  O  O25  1  0.285  0.255  0.545  1.0
  O  O26  1  0.017  0.875  0.758  1.0
  O  O27  1  0.875  0.758  0.017  1.0
  O  O28  1  0.500  0.000  0.000  1.0
  O  O29  1  0.319  0.542  0.988  1.0
  O  O30  1  0.000  0.000  0.500  1.0
  O  O31  1  0.542  0.988  0.319  1.0
  O  O32  1  0.255  0.545  0.285  1.0
  O  O33  1  0.000  0.500  0.000  1.0
  O  O34  1  0.125  0.242  0.983  1.0
[/CIF]
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The material structure described by Sr7Zr(Si2O7)3 crystallizes in the trigonal R-3 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to one O(1), one O(3), and three equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded to six equivalent O(1) atoms to form SrO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Zr(1) is bonded to six equivalent O(3) atoms to form ZrO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Sr(2)O6 octahedra,  a cornercorner with one Zr(1)O6 octahedra, and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Sr(2), and one Si(1) atom. In the second O site, O(2) is bonded to three equivalent Sr(1) and one Si(1) atom to form a mixture of distorted corner and edge-sharing OSr3Si tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Sr(1), one Zr(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr7Zr(Si2O7)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.518
_cell_length_b   8.518
_cell_length_c   8.518
_cell_angle_alpha   106.067
_cell_angle_beta   106.067
_cell_angle_gamma   106.067
_symmetry_Int_Tables_number   1
_cell_volume   527.237
_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
  Sr  Sr0  1  0.152  0.628  0.751  1.0
  Sr  Sr1  1  0.249  0.848  0.372  1.0
  Sr  Sr2  1  0.500  0.500  0.500  1.0
  Sr  Sr3  1  0.848  0.372  0.249  1.0
  Sr  Sr4  1  0.751  0.152  0.628  1.0
  Sr  Sr5  1  0.372  0.249  0.848  1.0
  Sr  Sr6  1  0.628  0.751  0.152  1.0
  Zr  Zr7  1  0.000  0.000  0.000  1.0
  Si  Si8  1  0.542  0.927  0.817  1.0
  Si  Si9  1  0.817  0.542  0.927  1.0
  Si  Si10  1  0.073  0.183  0.458  1.0
  Si  Si11  1  0.183  0.458  0.073  1.0
  Si  Si12  1  0.927  0.817  0.542  1.0
  Si  Si13  1  0.458  0.073  0.183  1.0
  O  O14  1  0.715  0.745  0.455  1.0
  O  O15  1  0.458  0.012  0.681  1.0
  O  O16  1  0.242  0.983  0.125  1.0
  O  O17  1  0.983  0.125  0.242  1.0
  O  O18  1  0.455  0.715  0.745  1.0
  O  O19  1  0.681  0.458  0.012  1.0
  O  O20  1  0.545  0.285  0.255  1.0
  O  O21  1  0.745  0.455  0.715  1.0
  O  O22  1  0.988  0.319  0.542  1.0
  O  O23  1  0.758  0.017  0.875  1.0
  O  O24  1  0.012  0.681  0.458  1.0
  O  O25  1  0.285  0.255  0.545  1.0
  O  O26  1  0.017  0.875  0.758  1.0
  O  O27  1  0.875  0.758  0.017  1.0
  O  O28  1  0.500  0.000  0.000  1.0
  O  O29  1  0.319  0.542  0.988  1.0
  O  O30  1  0.000  0.000  0.500  1.0
  O  O31  1  0.542  0.988  0.319  1.0
  O  O32  1  0.255  0.545  0.285  1.0
  O  O33  1  0.000  0.500  0.000  1.0
  O  O34  1  0.125  0.242  0.983  1.0
[/CIF]
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