The compound described by Sc3Hf2Si4 crystallizes in the tetragonal P4_12_12 space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to two equivalent Si(1) and four equivalent Si(2) atoms to form distorted corner-sharing ScSi6 octahedra. The corner-sharing octahedral tilt angles are 54°. In the second Sc site, Sc(2) is bonded in a 7-coordinate geometry to three equivalent Si(2) and four equivalent Si(1) atoms. Hf(1) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Sc(1), four equivalent Sc(2), three equivalent Hf(1), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Sc(1), three equivalent Sc(2), three equivalent Hf(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hf2Sc3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.171
_cell_length_b   7.171
_cell_length_c   12.995
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   668.176
_cell_formula_units_Z   4
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
  Hf  Hf0  1  0.642  0.499  0.876  1.0
  Hf  Hf1  1  0.358  0.501  0.376  1.0
  Hf  Hf2  1  0.999  0.858  0.626  1.0
  Hf  Hf3  1  0.001  0.142  0.126  1.0
  Hf  Hf4  1  0.501  0.358  0.624  1.0
  Hf  Hf5  1  0.499  0.642  0.124  1.0
  Hf  Hf6  1  0.858  0.999  0.374  1.0
  Hf  Hf7  1  0.142  0.001  0.874  1.0
  Sc  Sc8  1  0.823  0.177  0.750  1.0
  Sc  Sc9  1  0.177  0.823  0.250  1.0
  Sc  Sc10  1  0.677  0.677  0.500  1.0
  Sc  Sc11  1  0.323  0.323  0.000  1.0
  Sc  Sc12  1  0.846  0.496  0.285  1.0
  Sc  Sc13  1  0.154  0.504  0.785  1.0
  Sc  Sc14  1  0.996  0.654  0.035  1.0
  Sc  Sc15  1  0.004  0.346  0.535  1.0
  Sc  Sc16  1  0.504  0.154  0.215  1.0
  Sc  Sc17  1  0.496  0.846  0.715  1.0
  Sc  Sc18  1  0.654  0.996  0.965  1.0
  Sc  Sc19  1  0.346  0.004  0.465  1.0
  Si  Si20  1  0.709  0.356  0.074  1.0
  Si  Si21  1  0.291  0.644  0.574  1.0
  Si  Si22  1  0.856  0.791  0.824  1.0
  Si  Si23  1  0.144  0.209  0.324  1.0
  Si  Si24  1  0.644  0.291  0.426  1.0
  Si  Si25  1  0.356  0.709  0.926  1.0
  Si  Si26  1  0.791  0.856  0.176  1.0
  Si  Si27  1  0.209  0.144  0.676  1.0
  Si  Si28  1  0.800  0.552  0.686  1.0
  Si  Si29  1  0.200  0.448  0.186  1.0
  Si  Si30  1  0.052  0.700  0.436  1.0
  Si  Si31  1  0.948  0.300  0.936  1.0
  Si  Si32  1  0.448  0.200  0.814  1.0
  Si  Si33  1  0.552  0.800  0.314  1.0
  Si  Si34  1  0.700  0.052  0.564  1.0
  Si  Si35  1  0.300  0.948  0.064  1.0
[/CIF]
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The compound described by Sc3Hf2Si4 crystallizes in the tetragonal P4_12_12 space group. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to two equivalent Si(1) and four equivalent Si(2) atoms to form distorted corner-sharing ScSi6 octahedra. The corner-sharing octahedral tilt angles are 54°. In the second Sc site, Sc(2) is bonded in a 7-coordinate geometry to three equivalent Si(2) and four equivalent Si(1) atoms. Hf(1) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Sc(1), four equivalent Sc(2), three equivalent Hf(1), and one Si(2) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Sc(1), three equivalent Sc(2), three equivalent Hf(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hf2Sc3Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.171
_cell_length_b   7.171
_cell_length_c   12.995
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   668.176
_cell_formula_units_Z   4
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
  Hf  Hf0  1  0.642  0.499  0.876  1.0
  Hf  Hf1  1  0.358  0.501  0.376  1.0
  Hf  Hf2  1  0.999  0.858  0.626  1.0
  Hf  Hf3  1  0.001  0.142  0.126  1.0
  Hf  Hf4  1  0.501  0.358  0.624  1.0
  Hf  Hf5  1  0.499  0.642  0.124  1.0
  Hf  Hf6  1  0.858  0.999  0.374  1.0
  Hf  Hf7  1  0.142  0.001  0.874  1.0
  Sc  Sc8  1  0.823  0.177  0.750  1.0
  Sc  Sc9  1  0.177  0.823  0.250  1.0
  Sc  Sc10  1  0.677  0.677  0.500  1.0
  Sc  Sc11  1  0.323  0.323  0.000  1.0
  Sc  Sc12  1  0.846  0.496  0.285  1.0
  Sc  Sc13  1  0.154  0.504  0.785  1.0
  Sc  Sc14  1  0.996  0.654  0.035  1.0
  Sc  Sc15  1  0.004  0.346  0.535  1.0
  Sc  Sc16  1  0.504  0.154  0.215  1.0
  Sc  Sc17  1  0.496  0.846  0.715  1.0
  Sc  Sc18  1  0.654  0.996  0.965  1.0
  Sc  Sc19  1  0.346  0.004  0.465  1.0
  Si  Si20  1  0.709  0.356  0.074  1.0
  Si  Si21  1  0.291  0.644  0.574  1.0
  Si  Si22  1  0.856  0.791  0.824  1.0
  Si  Si23  1  0.144  0.209  0.324  1.0
  Si  Si24  1  0.644  0.291  0.426  1.0
  Si  Si25  1  0.356  0.709  0.926  1.0
  Si  Si26  1  0.791  0.856  0.176  1.0
  Si  Si27  1  0.209  0.144  0.676  1.0
  Si  Si28  1  0.800  0.552  0.686  1.0
  Si  Si29  1  0.200  0.448  0.186  1.0
  Si  Si30  1  0.052  0.700  0.436  1.0
  Si  Si31  1  0.948  0.300  0.936  1.0
  Si  Si32  1  0.448  0.200  0.814  1.0
  Si  Si33  1  0.552  0.800  0.314  1.0
  Si  Si34  1  0.700  0.052  0.564  1.0
  Si  Si35  1  0.300  0.948  0.064  1.0
[/CIF]
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