The material described by SrSc4(Si2O7)(Si3O10) crystallizes in the monoclinic P2_1/m space group. Sr(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to one O(10), one O(6), two equivalent O(5), and two equivalent O(8) atoms to form distorted ScO6 pentagonal pyramids that share corners with three equivalent Si(2)O4 tetrahedra, corners with three equivalent Si(3)O4 tetrahedra,  an edgeedge with one Sc(2)O6 octahedra, and edges with two equivalent Sc(1)O6 pentagonal pyramids. In the second Sc site, Sc(2) is bonded to one O(1), one O(10), one O(2), one O(4), one O(6), and one O(7) atom to form distorted ScO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  an edgeedge with one Sc(2)O6 octahedra, and  an edgeedge with one Sc(1)O6 pentagonal pyramid. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with four equivalent Sc(2)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(2)O6 octahedra, corners with three equivalent Sc(1)O6 pentagonal pyramids, and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. In the third Si site, Si(3) is bonded to one O(10), one O(7), one O(8), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(2)O6 octahedra, corners with three equivalent Sc(1)O6 pentagonal pyramids, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-59°. There are ten inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Sc(1) and one Si(2) atom. In the second O site, O(6) is bonded in a distorted trigonal planar geometry to one Sc(1), one Sc(2), and one Si(2) atom. In the third O site, O(7) is bonded in a 3-coordinate geometry to one Sr(1), one Sc(2), and one Si(3) atom. In the fourth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Sc(1) and one Si(3) atom. In the fifth O site, O(9) is bonded in a linear geometry to two equivalent Si(3) atoms. In the sixth O site, O(10) is bonded in a trigonal planar geometry to one Sc(1), one Sc(2), and one Si(3) atom. In the seventh O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Sc(2), and one Si(1) atom. In the eighth O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Sc(2), and one Si(1) atom. In the ninth O site, O(3) is bonded in a 2-coordinate geometry to one Sr(1), one Si(1), and one Si(2) atom. In the tenth O site, O(4) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sc(2), and one Si(2) atom. is represented by the CIF file [CIF]
data_SrSc4Si5O17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   19.451
_cell_length_b   5.333
_cell_length_c   6.633
_cell_angle_alpha   73.434
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   659.440
_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  0.250  0.767  0.777  1.0
  Sr  Sr1  1  0.750  0.233  0.223  1.0
  Sc  Sc2  1  0.038  0.696  0.112  1.0
  Sc  Sc3  1  0.538  0.304  0.888  1.0
  Sc  Sc4  1  0.962  0.304  0.888  1.0
  Sc  Sc5  1  0.462  0.696  0.112  1.0
  Sc  Sc6  1  0.160  0.358  0.462  1.0
  Sc  Sc7  1  0.660  0.642  0.538  1.0
  Sc  Sc8  1  0.840  0.642  0.538  1.0
  Sc  Sc9  1  0.340  0.358  0.462  1.0
  Si  Si10  1  0.250  0.938  0.258  1.0
  Si  Si11  1  0.750  0.062  0.742  1.0
  Si  Si12  1  0.133  0.235  0.985  1.0
  Si  Si13  1  0.633  0.765  0.015  1.0
  Si  Si14  1  0.867  0.765  0.015  1.0
  Si  Si15  1  0.367  0.235  0.985  1.0
  Si  Si16  1  0.063  0.802  0.591  1.0
  Si  Si17  1  0.563  0.198  0.409  1.0
  Si  Si18  1  0.937  0.198  0.409  1.0
  Si  Si19  1  0.437  0.802  0.591  1.0
  O  O20  1  0.250  0.150  0.396  1.0
  O  O21  1  0.750  0.850  0.604  1.0
  O  O22  1  0.250  0.637  0.408  1.0
  O  O23  1  0.750  0.363  0.592  1.0
  O  O24  1  0.183  0.978  0.099  1.0
  O  O25  1  0.683  0.022  0.901  1.0
  O  O26  1  0.817  0.022  0.901  1.0
  O  O27  1  0.317  0.978  0.099  1.0
  O  O28  1  0.171  0.389  0.766  1.0
  O  O29  1  0.671  0.611  0.234  1.0
  O  O30  1  0.829  0.611  0.234  1.0
  O  O31  1  0.329  0.389  0.766  1.0
  O  O32  1  0.060  0.092  0.967  1.0
  O  O33  1  0.560  0.908  0.033  1.0
  O  O34  1  0.940  0.908  0.033  1.0
  O  O35  1  0.440  0.092  0.967  1.0
  O  O36  1  0.127  0.422  0.145  1.0
  O  O37  1  0.627  0.578  0.855  1.0
  O  O38  1  0.873  0.578  0.855  1.0
  O  O39  1  0.373  0.422  0.145  1.0
  O  O40  1  0.132  0.973  0.602  1.0
  O  O41  1  0.632  0.027  0.398  1.0
  O  O42  1  0.868  0.027  0.398  1.0
  O  O43  1  0.368  0.973  0.602  1.0
  O  O44  1  0.035  0.615  0.819  1.0
  O  O45  1  0.535  0.385  0.181  1.0
  O  O46  1  0.965  0.385  0.181  1.0
  O  O47  1  0.465  0.615  0.819  1.0
  O  O48  1  0.000  0.000  0.500  1.0
  O  O49  1  0.500  0.000  0.500  1.0
  O  O50  1  0.075  0.627  0.424  1.0
  O  O51  1  0.575  0.373  0.576  1.0
  O  O52  1  0.925  0.373  0.576  1.0
  O  O53  1  0.425  0.627  0.424  1.0
[/CIF]
.
The material described by SrSc4(Si2O7)(Si3O10) crystallizes in the monoclinic P2_1/m space group. Sr(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to one O(10), one O(6), two equivalent O(5), and two equivalent O(8) atoms to form distorted ScO6 pentagonal pyramids that share corners with three equivalent Si(2)O4 tetrahedra, corners with three equivalent Si(3)O4 tetrahedra,  an edgeedge with one Sc(2)O6 octahedra, and edges with two equivalent Sc(1)O6 pentagonal pyramids. In the second Sc site, Sc(2) is bonded to one O(1), one O(10), one O(2), one O(4), one O(6), and one O(7) atom to form distorted ScO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  an edgeedge with one Sc(2)O6 octahedra, and  an edgeedge with one Sc(1)O6 pentagonal pyramid. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with four equivalent Sc(2)O6 octahedra and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the second Si site, Si(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(2)O6 octahedra, corners with three equivalent Sc(1)O6 pentagonal pyramids, and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. In the third Si site, Si(3) is bonded to one O(10), one O(7), one O(8), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(2)O6 octahedra, corners with three equivalent Sc(1)O6 pentagonal pyramids, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-59°. There are ten inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Sc(1) and one Si(2) atom. In the second O site, O(6) is bonded in a distorted trigonal planar geometry to one Sc(1), one Sc(2), and one Si(2) atom. In the third O site, O(7) is bonded in a 3-coordinate geometry to one Sr(1), one Sc(2), and one Si(3) atom. In the fourth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Sc(1) and one Si(3) atom. In the fifth O site, O(9) is bonded in a linear geometry to two equivalent Si(3) atoms. In the sixth O site, O(10) is bonded in a trigonal planar geometry to one Sc(1), one Sc(2), and one Si(3) atom. In the seventh O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Sc(2), and one Si(1) atom. In the eighth O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Sc(2), and one Si(1) atom. In the ninth O site, O(3) is bonded in a 2-coordinate geometry to one Sr(1), one Si(1), and one Si(2) atom. In the tenth O site, O(4) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sc(2), and one Si(2) atom. is represented by the CIF file [CIF]
data_SrSc4Si5O17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   19.451
_cell_length_b   5.333
_cell_length_c   6.633
_cell_angle_alpha   73.434
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   659.440
_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  0.250  0.767  0.777  1.0
  Sr  Sr1  1  0.750  0.233  0.223  1.0
  Sc  Sc2  1  0.038  0.696  0.112  1.0
  Sc  Sc3  1  0.538  0.304  0.888  1.0
  Sc  Sc4  1  0.962  0.304  0.888  1.0
  Sc  Sc5  1  0.462  0.696  0.112  1.0
  Sc  Sc6  1  0.160  0.358  0.462  1.0
  Sc  Sc7  1  0.660  0.642  0.538  1.0
  Sc  Sc8  1  0.840  0.642  0.538  1.0
  Sc  Sc9  1  0.340  0.358  0.462  1.0
  Si  Si10  1  0.250  0.938  0.258  1.0
  Si  Si11  1  0.750  0.062  0.742  1.0
  Si  Si12  1  0.133  0.235  0.985  1.0
  Si  Si13  1  0.633  0.765  0.015  1.0
  Si  Si14  1  0.867  0.765  0.015  1.0
  Si  Si15  1  0.367  0.235  0.985  1.0
  Si  Si16  1  0.063  0.802  0.591  1.0
  Si  Si17  1  0.563  0.198  0.409  1.0
  Si  Si18  1  0.937  0.198  0.409  1.0
  Si  Si19  1  0.437  0.802  0.591  1.0
  O  O20  1  0.250  0.150  0.396  1.0
  O  O21  1  0.750  0.850  0.604  1.0
  O  O22  1  0.250  0.637  0.408  1.0
  O  O23  1  0.750  0.363  0.592  1.0
  O  O24  1  0.183  0.978  0.099  1.0
  O  O25  1  0.683  0.022  0.901  1.0
  O  O26  1  0.817  0.022  0.901  1.0
  O  O27  1  0.317  0.978  0.099  1.0
  O  O28  1  0.171  0.389  0.766  1.0
  O  O29  1  0.671  0.611  0.234  1.0
  O  O30  1  0.829  0.611  0.234  1.0
  O  O31  1  0.329  0.389  0.766  1.0
  O  O32  1  0.060  0.092  0.967  1.0
  O  O33  1  0.560  0.908  0.033  1.0
  O  O34  1  0.940  0.908  0.033  1.0
  O  O35  1  0.440  0.092  0.967  1.0
  O  O36  1  0.127  0.422  0.145  1.0
  O  O37  1  0.627  0.578  0.855  1.0
  O  O38  1  0.873  0.578  0.855  1.0
  O  O39  1  0.373  0.422  0.145  1.0
  O  O40  1  0.132  0.973  0.602  1.0
  O  O41  1  0.632  0.027  0.398  1.0
  O  O42  1  0.868  0.027  0.398  1.0
  O  O43  1  0.368  0.973  0.602  1.0
  O  O44  1  0.035  0.615  0.819  1.0
  O  O45  1  0.535  0.385  0.181  1.0
  O  O46  1  0.965  0.385  0.181  1.0
  O  O47  1  0.465  0.615  0.819  1.0
  O  O48  1  0.000  0.000  0.500  1.0
  O  O49  1  0.500  0.000  0.500  1.0
  O  O50  1  0.075  0.627  0.424  1.0
  O  O51  1  0.575  0.373  0.576  1.0
  O  O52  1  0.925  0.373  0.576  1.0
  O  O53  1  0.425  0.627  0.424  1.0
[/CIF]
.