The compound described by Pm3Hf is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pm sites. In the first Pm site, Pm(1) is bonded to four equivalent Pm(1), four equivalent Pm(2), and four equivalent Hf(1) atoms to form PmPm8Hf4 cuboctahedra that share corners with twelve equivalent Pm(1)Pm8Hf4 cuboctahedra, edges with eight equivalent Pm(1)Pm8Hf4 cuboctahedra, edges with eight equivalent Pm(2)Pm8Hf4 cuboctahedra, edges with eight equivalent Hf(1)Pm12 cuboctahedra, faces with four equivalent Pm(2)Pm8Hf4 cuboctahedra, faces with four equivalent Hf(1)Pm12 cuboctahedra, and faces with ten equivalent Pm(1)Pm8Hf4 cuboctahedra. In the second Pm site, Pm(2) is bonded to eight equivalent Pm(1) and four equivalent Hf(1) atoms to form PmPm8Hf4 cuboctahedra that share corners with four equivalent Pm(2)Pm8Hf4 cuboctahedra, corners with eight equivalent Hf(1)Pm12 cuboctahedra, edges with eight equivalent Pm(2)Pm8Hf4 cuboctahedra, edges with sixteen equivalent Pm(1)Pm8Hf4 cuboctahedra, faces with four equivalent Pm(2)Pm8Hf4 cuboctahedra, faces with six equivalent Hf(1)Pm12 cuboctahedra, and faces with eight equivalent Pm(1)Pm8Hf4 cuboctahedra. Hf(1) is bonded to four equivalent Pm(2) and eight equivalent Pm(1) atoms to form HfPm12 cuboctahedra that share corners with four equivalent Hf(1)Pm12 cuboctahedra, corners with eight equivalent Pm(2)Pm8Hf4 cuboctahedra, edges with eight equivalent Hf(1)Pm12 cuboctahedra, edges with sixteen equivalent Pm(1)Pm8Hf4 cuboctahedra, faces with four equivalent Hf(1)Pm12 cuboctahedra, faces with six equivalent Pm(2)Pm8Hf4 cuboctahedra, and faces with eight equivalent Pm(1)Pm8Hf4 cuboctahedra. is represented by the CIF file [CIF]
data_Pm3Hf
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.073
_cell_length_b   6.073
_cell_length_c   6.073
_cell_angle_alpha   131.695
_cell_angle_beta   131.695
_cell_angle_gamma   70.711
_symmetry_Int_Tables_number   1
_cell_volume   122.319
_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
  Pm  Pm0  1  0.750  0.250  0.500  1.0
  Pm  Pm1  1  0.250  0.750  0.500  1.0
  Pm  Pm2  1  0.500  0.500  0.000  1.0
  Hf  Hf3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by Pm3Hf is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pm sites. In the first Pm site, Pm(1) is bonded to four equivalent Pm(1), four equivalent Pm(2), and four equivalent Hf(1) atoms to form PmPm8Hf4 cuboctahedra that share corners with twelve equivalent Pm(1)Pm8Hf4 cuboctahedra, edges with eight equivalent Pm(1)Pm8Hf4 cuboctahedra, edges with eight equivalent Pm(2)Pm8Hf4 cuboctahedra, edges with eight equivalent Hf(1)Pm12 cuboctahedra, faces with four equivalent Pm(2)Pm8Hf4 cuboctahedra, faces with four equivalent Hf(1)Pm12 cuboctahedra, and faces with ten equivalent Pm(1)Pm8Hf4 cuboctahedra. In the second Pm site, Pm(2) is bonded to eight equivalent Pm(1) and four equivalent Hf(1) atoms to form PmPm8Hf4 cuboctahedra that share corners with four equivalent Pm(2)Pm8Hf4 cuboctahedra, corners with eight equivalent Hf(1)Pm12 cuboctahedra, edges with eight equivalent Pm(2)Pm8Hf4 cuboctahedra, edges with sixteen equivalent Pm(1)Pm8Hf4 cuboctahedra, faces with four equivalent Pm(2)Pm8Hf4 cuboctahedra, faces with six equivalent Hf(1)Pm12 cuboctahedra, and faces with eight equivalent Pm(1)Pm8Hf4 cuboctahedra. Hf(1) is bonded to four equivalent Pm(2) and eight equivalent Pm(1) atoms to form HfPm12 cuboctahedra that share corners with four equivalent Hf(1)Pm12 cuboctahedra, corners with eight equivalent Pm(2)Pm8Hf4 cuboctahedra, edges with eight equivalent Hf(1)Pm12 cuboctahedra, edges with sixteen equivalent Pm(1)Pm8Hf4 cuboctahedra, faces with four equivalent Hf(1)Pm12 cuboctahedra, faces with six equivalent Pm(2)Pm8Hf4 cuboctahedra, and faces with eight equivalent Pm(1)Pm8Hf4 cuboctahedra. is represented by the CIF file [CIF]
data_Pm3Hf
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.073
_cell_length_b   6.073
_cell_length_c   6.073
_cell_angle_alpha   131.695
_cell_angle_beta   131.695
_cell_angle_gamma   70.711
_symmetry_Int_Tables_number   1
_cell_volume   122.319
_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
  Pm  Pm0  1  0.750  0.250  0.500  1.0
  Pm  Pm1  1  0.250  0.750  0.500  1.0
  Pm  Pm2  1  0.500  0.500  0.000  1.0
  Hf  Hf3  1  0.000  0.000  0.000  1.0
[/CIF]
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