The compound described by PrMg2Ni9 crystallizes in the trigonal R-3m space group. Mg(1) is bonded in a 12-coordinate geometry to three equivalent Ni(3) and nine equivalent Ni(1) atoms. Pr(1) is bonded in a distorted hexagonal planar geometry to six equivalent Ni(2) and twelve equivalent Ni(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to three equivalent Mg(1), two equivalent Pr(1), one Ni(3), two equivalent Ni(2), and four equivalent Ni(1) atoms to form NiPr2Mg3Ni7 cuboctahedra that share corners with two equivalent Ni(3)Mg6Ni6 cuboctahedra, corners with fifteen equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra, edges with eight equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra, faces with three equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eleven equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra. In the second Ni site, Ni(2) is bonded in a 12-coordinate geometry to three equivalent Pr(1), three equivalent Ni(2), and six equivalent Ni(1) atoms. In the third Ni site, Ni(3) is bonded to six equivalent Mg(1) and six equivalent Ni(1) atoms to form NiMg6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra, edges with six equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra. is represented by the CIF card [CIF]
data_PrMg2Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.301
_cell_length_b   8.301
_cell_length_c   8.301
_cell_angle_alpha   34.044
_cell_angle_beta   34.044
_cell_angle_gamma   34.044
_symmetry_Int_Tables_number   1
_cell_volume   159.811
_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
  Pr  Pr0  1  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.855  0.855  0.855  1.0
  Mg  Mg2  1  0.145  0.145  0.145  1.0
  Ni  Ni3  1  0.082  0.586  0.586  1.0
  Ni  Ni4  1  0.918  0.414  0.414  1.0
  Ni  Ni5  1  0.666  0.666  0.666  1.0
  Ni  Ni6  1  0.586  0.586  0.082  1.0
  Ni  Ni7  1  0.414  0.918  0.414  1.0
  Ni  Ni8  1  0.334  0.334  0.334  1.0
  Ni  Ni9  1  0.500  0.500  0.500  1.0
  Ni  Ni10  1  0.414  0.414  0.918  1.0
  Ni  Ni11  1  0.586  0.082  0.586  1.0
[/CIF]
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The compound described by PrMg2Ni9 crystallizes in the trigonal R-3m space group. Mg(1) is bonded in a 12-coordinate geometry to three equivalent Ni(3) and nine equivalent Ni(1) atoms. Pr(1) is bonded in a distorted hexagonal planar geometry to six equivalent Ni(2) and twelve equivalent Ni(1) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to three equivalent Mg(1), two equivalent Pr(1), one Ni(3), two equivalent Ni(2), and four equivalent Ni(1) atoms to form NiPr2Mg3Ni7 cuboctahedra that share corners with two equivalent Ni(3)Mg6Ni6 cuboctahedra, corners with fifteen equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra, edges with eight equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra, faces with three equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eleven equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra. In the second Ni site, Ni(2) is bonded in a 12-coordinate geometry to three equivalent Pr(1), three equivalent Ni(2), and six equivalent Ni(1) atoms. In the third Ni site, Ni(3) is bonded to six equivalent Mg(1) and six equivalent Ni(1) atoms to form NiMg6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra, edges with six equivalent Ni(3)Mg6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Pr2Mg3Ni7 cuboctahedra. is represented by the CIF card [CIF]
data_PrMg2Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.301
_cell_length_b   8.301
_cell_length_c   8.301
_cell_angle_alpha   34.044
_cell_angle_beta   34.044
_cell_angle_gamma   34.044
_symmetry_Int_Tables_number   1
_cell_volume   159.811
_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
  Pr  Pr0  1  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.855  0.855  0.855  1.0
  Mg  Mg2  1  0.145  0.145  0.145  1.0
  Ni  Ni3  1  0.082  0.586  0.586  1.0
  Ni  Ni4  1  0.918  0.414  0.414  1.0
  Ni  Ni5  1  0.666  0.666  0.666  1.0
  Ni  Ni6  1  0.586  0.586  0.082  1.0
  Ni  Ni7  1  0.414  0.918  0.414  1.0
  Ni  Ni8  1  0.334  0.334  0.334  1.0
  Ni  Ni9  1  0.500  0.500  0.500  1.0
  Ni  Ni10  1  0.414  0.414  0.918  1.0
  Ni  Ni11  1  0.586  0.082  0.586  1.0
[/CIF]
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