The structure described by K3ScSi2O7 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to nine equivalent O(1) atoms. In the second K site, K(2) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. Sc(1) is bonded to six equivalent O(1) atoms to form ScO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(2) and three equivalent O(1) atoms to form SiO4 tetrahedra that share corners with three equivalent Sc(1)O6 octahedra and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(2), three equivalent K(1), one Sc(1), and one Si(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3ScSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.681
_cell_length_b   5.681
_cell_length_c   13.844
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   386.914
_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
  K  K0  1  0.333  0.667  0.407  1.0
  K  K1  1  0.000  0.000  0.250  1.0
  K  K2  1  0.667  0.333  0.593  1.0
  K  K3  1  0.333  0.667  0.093  1.0
  K  K4  1  0.667  0.333  0.907  1.0
  K  K5  1  0.000  0.000  0.750  1.0
  Sc  Sc6  1  0.000  0.000  0.500  1.0
  Sc  Sc7  1  0.000  0.000  0.000  1.0
  Si  Si8  1  0.333  0.667  0.629  1.0
  Si  Si9  1  0.667  0.333  0.371  1.0
  Si  Si10  1  0.667  0.333  0.129  1.0
  Si  Si11  1  0.333  0.667  0.871  1.0
  O  O12  1  0.350  0.175  0.408  1.0
  O  O13  1  0.825  0.175  0.092  1.0
  O  O14  1  0.175  0.350  0.592  1.0
  O  O15  1  0.175  0.825  0.908  1.0
  O  O16  1  0.650  0.825  0.908  1.0
  O  O17  1  0.650  0.825  0.592  1.0
  O  O18  1  0.350  0.175  0.092  1.0
  O  O19  1  0.175  0.825  0.592  1.0
  O  O20  1  0.825  0.175  0.408  1.0
  O  O21  1  0.175  0.350  0.908  1.0
  O  O22  1  0.825  0.650  0.092  1.0
  O  O23  1  0.825  0.650  0.408  1.0
  O  O24  1  0.667  0.333  0.250  1.0
  O  O25  1  0.333  0.667  0.750  1.0
[/CIF]
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The structure described by K3ScSi2O7 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to nine equivalent O(1) atoms. In the second K site, K(2) is bonded in a 6-coordinate geometry to six equivalent O(1) atoms. Sc(1) is bonded to six equivalent O(1) atoms to form ScO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(2) and three equivalent O(1) atoms to form SiO4 tetrahedra that share corners with three equivalent Sc(1)O6 octahedra and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(2), three equivalent K(1), one Sc(1), and one Si(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3ScSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.681
_cell_length_b   5.681
_cell_length_c   13.844
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   386.914
_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
  K  K0  1  0.333  0.667  0.407  1.0
  K  K1  1  0.000  0.000  0.250  1.0
  K  K2  1  0.667  0.333  0.593  1.0
  K  K3  1  0.333  0.667  0.093  1.0
  K  K4  1  0.667  0.333  0.907  1.0
  K  K5  1  0.000  0.000  0.750  1.0
  Sc  Sc6  1  0.000  0.000  0.500  1.0
  Sc  Sc7  1  0.000  0.000  0.000  1.0
  Si  Si8  1  0.333  0.667  0.629  1.0
  Si  Si9  1  0.667  0.333  0.371  1.0
  Si  Si10  1  0.667  0.333  0.129  1.0
  Si  Si11  1  0.333  0.667  0.871  1.0
  O  O12  1  0.350  0.175  0.408  1.0
  O  O13  1  0.825  0.175  0.092  1.0
  O  O14  1  0.175  0.350  0.592  1.0
  O  O15  1  0.175  0.825  0.908  1.0
  O  O16  1  0.650  0.825  0.908  1.0
  O  O17  1  0.650  0.825  0.592  1.0
  O  O18  1  0.350  0.175  0.092  1.0
  O  O19  1  0.175  0.825  0.592  1.0
  O  O20  1  0.825  0.175  0.408  1.0
  O  O21  1  0.175  0.350  0.908  1.0
  O  O22  1  0.825  0.650  0.092  1.0
  O  O23  1  0.825  0.650  0.408  1.0
  O  O24  1  0.667  0.333  0.250  1.0
  O  O25  1  0.333  0.667  0.750  1.0
[/CIF]
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