The material described by LiSc4(Si2O7)2 crystallizes in the trigonal R3m space group. Li(1) is bonded in a 7-coordinate geometry to one O(5), three equivalent O(3), and three equivalent O(4) atoms. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 5-coordinate geometry to one O(1), one O(5), one O(6), two equivalent O(2), and two equivalent O(3) atoms. In the second Sc site, Sc(2) is bonded to one O(5), one O(6), three equivalent O(1), and three equivalent O(4) atoms to form distorted ScO8 hexagonal bipyramids that share edges with six equivalent Si(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form SiO6 octahedra that share corners with two equivalent Si(2)O6 octahedra, corners with four equivalent Si(1)O6 octahedra, and edges with two equivalent Sc(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-47°. In the second Si site, Si(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form corner-sharing SiO6 octahedra. The corner-sharing octahedral tilt angles range from 44-47°. There are six inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Li(1), one Sc(2), and two equivalent Si(1) atoms. In the second O site, O(5) is bonded to one Li(1), one Sc(2), and three equivalent Sc(1) atoms to form distorted OLiSc4 trigonal bipyramids that share corners with six equivalent O(2)Sc2Si2 tetrahedra and corners with four equivalent O(6)Sc4 trigonal pyramids. In the third O site, O(6) is bonded to one Sc(2) and three equivalent Sc(1) atoms to form distorted OSc4 trigonal pyramids that share corners with four equivalent O(5)LiSc4 trigonal bipyramids and edges with three equivalent O(2)Sc2Si2 tetrahedra. In the fourth O site, O(1) is bonded in a 4-coordinate geometry to one Sc(1), one Sc(2), and two equivalent Si(1) atoms. In the fifth O site, O(2) is bonded to two equivalent Sc(1), one Si(1), and one Si(2) atom to form distorted OSc2Si2 tetrahedra that share corners with four equivalent O(2)Sc2Si2 tetrahedra, corners with two equivalent O(5)LiSc4 trigonal bipyramids, and  an edgeedge with one O(6)Sc4 trigonal pyramid. In the sixth O site, O(3) is bonded in a 5-coordinate geometry to one Li(1), two equivalent Sc(1), one Si(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiSc4(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.773
_cell_length_b   6.773
_cell_length_c   6.773
_cell_angle_alpha   58.612
_cell_angle_beta   58.612
_cell_angle_gamma   58.612
_symmetry_Int_Tables_number   1
_cell_volume   212.722
_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
  Li  Li0  1  0.243  0.243  0.243  1.0
  Sc  Sc1  1  0.975  0.512  0.975  1.0
  Sc  Sc2  1  0.512  0.975  0.975  1.0
  Sc  Sc3  1  0.975  0.975  0.512  1.0
  Sc  Sc4  1  0.002  0.002  0.002  1.0
  Si  Si5  1  0.501  0.998  0.501  1.0
  Si  Si6  1  0.998  0.501  0.501  1.0
  Si  Si7  1  0.501  0.501  0.998  1.0
  Si  Si8  1  0.504  0.504  0.504  1.0
  O  O9  1  0.426  0.822  0.822  1.0
  O  O10  1  0.174  0.576  0.576  1.0
  O  O11  1  0.822  0.426  0.822  1.0
  O  O12  1  0.822  0.822  0.426  1.0
  O  O13  1  0.426  0.426  0.828  1.0
  O  O14  1  0.426  0.828  0.426  1.0
  O  O15  1  0.183  0.575  0.183  1.0
  O  O16  1  0.576  0.174  0.576  1.0
  O  O17  1  0.128  0.128  0.128  1.0
  O  O18  1  0.883  0.883  0.883  1.0
  O  O19  1  0.828  0.426  0.426  1.0
  O  O20  1  0.576  0.576  0.174  1.0
  O  O21  1  0.183  0.183  0.575  1.0
  O  O22  1  0.575  0.183  0.183  1.0
[/CIF]
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The material described by LiSc4(Si2O7)2 crystallizes in the trigonal R3m space group. Li(1) is bonded in a 7-coordinate geometry to one O(5), three equivalent O(3), and three equivalent O(4) atoms. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded in a 5-coordinate geometry to one O(1), one O(5), one O(6), two equivalent O(2), and two equivalent O(3) atoms. In the second Sc site, Sc(2) is bonded to one O(5), one O(6), three equivalent O(1), and three equivalent O(4) atoms to form distorted ScO8 hexagonal bipyramids that share edges with six equivalent Si(1)O6 octahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form SiO6 octahedra that share corners with two equivalent Si(2)O6 octahedra, corners with four equivalent Si(1)O6 octahedra, and edges with two equivalent Sc(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-47°. In the second Si site, Si(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form corner-sharing SiO6 octahedra. The corner-sharing octahedral tilt angles range from 44-47°. There are six inequivalent O sites. In the first O site, O(4) is bonded in a 3-coordinate geometry to one Li(1), one Sc(2), and two equivalent Si(1) atoms. In the second O site, O(5) is bonded to one Li(1), one Sc(2), and three equivalent Sc(1) atoms to form distorted OLiSc4 trigonal bipyramids that share corners with six equivalent O(2)Sc2Si2 tetrahedra and corners with four equivalent O(6)Sc4 trigonal pyramids. In the third O site, O(6) is bonded to one Sc(2) and three equivalent Sc(1) atoms to form distorted OSc4 trigonal pyramids that share corners with four equivalent O(5)LiSc4 trigonal bipyramids and edges with three equivalent O(2)Sc2Si2 tetrahedra. In the fourth O site, O(1) is bonded in a 4-coordinate geometry to one Sc(1), one Sc(2), and two equivalent Si(1) atoms. In the fifth O site, O(2) is bonded to two equivalent Sc(1), one Si(1), and one Si(2) atom to form distorted OSc2Si2 tetrahedra that share corners with four equivalent O(2)Sc2Si2 tetrahedra, corners with two equivalent O(5)LiSc4 trigonal bipyramids, and  an edgeedge with one O(6)Sc4 trigonal pyramid. In the sixth O site, O(3) is bonded in a 5-coordinate geometry to one Li(1), two equivalent Sc(1), one Si(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiSc4(Si2O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.773
_cell_length_b   6.773
_cell_length_c   6.773
_cell_angle_alpha   58.612
_cell_angle_beta   58.612
_cell_angle_gamma   58.612
_symmetry_Int_Tables_number   1
_cell_volume   212.722
_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
  Li  Li0  1  0.243  0.243  0.243  1.0
  Sc  Sc1  1  0.975  0.512  0.975  1.0
  Sc  Sc2  1  0.512  0.975  0.975  1.0
  Sc  Sc3  1  0.975  0.975  0.512  1.0
  Sc  Sc4  1  0.002  0.002  0.002  1.0
  Si  Si5  1  0.501  0.998  0.501  1.0
  Si  Si6  1  0.998  0.501  0.501  1.0
  Si  Si7  1  0.501  0.501  0.998  1.0
  Si  Si8  1  0.504  0.504  0.504  1.0
  O  O9  1  0.426  0.822  0.822  1.0
  O  O10  1  0.174  0.576  0.576  1.0
  O  O11  1  0.822  0.426  0.822  1.0
  O  O12  1  0.822  0.822  0.426  1.0
  O  O13  1  0.426  0.426  0.828  1.0
  O  O14  1  0.426  0.828  0.426  1.0
  O  O15  1  0.183  0.575  0.183  1.0
  O  O16  1  0.576  0.174  0.576  1.0
  O  O17  1  0.128  0.128  0.128  1.0
  O  O18  1  0.883  0.883  0.883  1.0
  O  O19  1  0.828  0.426  0.426  1.0
  O  O20  1  0.576  0.576  0.174  1.0
  O  O21  1  0.183  0.183  0.575  1.0
  O  O22  1  0.575  0.183  0.183  1.0
[/CIF]
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