The crystal structure described by Yb2Ni7 crystallizes in the trigonal R-3m space group. There are five inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the second Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the third Yb site, Yb(2) is bonded in a 12-coordinate geometry to three equivalent Ni(1) and nine equivalent Ni(5) atoms. In the fourth Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the fifth Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(4) is bonded to four Yb(1,1); two equivalent Ni(2); two equivalent Ni(3); and four equivalent Ni(4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra, edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra, faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Yb4Ni8 cuboctahedra. In the second Ni site, Ni(1) is bonded to six equivalent Yb(2) and six equivalent Ni(5) atoms to form NiYb6Ni6 cuboctahedra that share corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra, edges with six equivalent Ni(1)Yb6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(5)Yb5Ni7 cuboctahedra. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Yb(1); three Ni(4,4); and three equivalent Ni(5) atoms. In the fourth Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Yb(1); three Ni(4,4); and three equivalent Ni(5) atoms. In the fifth Ni site, Ni(4) is bonded to four equivalent Yb(1), two equivalent Ni(2), two equivalent Ni(3), and four equivalent Ni(4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra, edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra, faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Yb4Ni8 cuboctahedra. In the sixth Ni site, Ni(4) is bonded to four equivalent Yb(1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra; edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra; faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra; and faces with eight Ni(4,4)Yb4Ni8 cuboctahedra. In the seventh Ni site, Ni(5) is bonded to two equivalent Yb(1), three equivalent Yb(2), one Ni(1), one Ni(2), one Ni(3), and four equivalent Ni(5) atoms to form distorted NiYb5Ni7 cuboctahedra that share corners with two equivalent Ni(1)Yb6Ni6 cuboctahedra; corners with six Ni(4,4)Yb4Ni8 cuboctahedra; corners with nine equivalent Ni(5)Yb5Ni7 cuboctahedra; edges with four Ni(4,4)Yb4Ni8 cuboctahedra; edges with four equivalent Ni(5)Yb5Ni7 cuboctahedra;  a faceface with one Ni(4)Yb4Ni8 cuboctahedra; faces with three equivalent Ni(1)Yb6Ni6 cuboctahedra; and faces with ten equivalent Ni(5)Yb5Ni7 cuboctahedra. In the eighth Ni site, Ni(4) is bonded to four Yb(1,1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra; edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra; faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra; and faces with eight Ni(4,4)Yb4Ni8 cuboctahedra. is represented by the CIF card [CIF]
data_Yb2Ni7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.879
_cell_length_b   4.879
_cell_length_c   12.152
_cell_angle_alpha   78.419
_cell_angle_beta   78.419
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   243.709
_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
  Yb  Yb0  1  0.948  0.948  0.155  1.0
  Yb  Yb1  1  0.052  0.052  0.845  1.0
  Yb  Yb2  1  0.853  0.853  0.442  1.0
  Yb  Yb3  1  0.147  0.147  0.558  1.0
  Ni  Ni4  1  0.500  0.500  0.500  1.0
  Ni  Ni5  1  0.722  0.722  0.833  1.0
  Ni  Ni6  1  0.278  0.278  0.167  1.0
  Ni  Ni7  1  0.611  0.611  0.166  1.0
  Ni  Ni8  1  0.389  0.389  0.834  1.0
  Ni  Ni9  1  0.000  0.500  0.000  1.0
  Ni  Ni10  1  0.500  0.000  0.000  1.0
  Ni  Ni11  1  0.500  0.500  0.000  1.0
  Ni  Ni12  1  0.388  0.388  0.332  1.0
  Ni  Ni13  1  0.891  0.388  0.332  1.0
  Ni  Ni14  1  0.388  0.891  0.332  1.0
  Ni  Ni15  1  0.612  0.612  0.668  1.0
  Ni  Ni16  1  0.109  0.612  0.668  1.0
  Ni  Ni17  1  0.612  0.109  0.668  1.0
[/CIF]
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The crystal structure described by Yb2Ni7 crystallizes in the trigonal R-3m space group. There are five inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the second Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the third Yb site, Yb(2) is bonded in a 12-coordinate geometry to three equivalent Ni(1) and nine equivalent Ni(5) atoms. In the fourth Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. In the fifth Yb site, Yb(1) is bonded in a 6-coordinate geometry to three equivalent Ni(2); three equivalent Ni(3); six Ni(4,4); and six equivalent Ni(5) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(4) is bonded to four Yb(1,1); two equivalent Ni(2); two equivalent Ni(3); and four equivalent Ni(4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra, edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra, faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Yb4Ni8 cuboctahedra. In the second Ni site, Ni(1) is bonded to six equivalent Yb(2) and six equivalent Ni(5) atoms to form NiYb6Ni6 cuboctahedra that share corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra, edges with six equivalent Ni(1)Yb6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(5)Yb5Ni7 cuboctahedra. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Yb(1); three Ni(4,4); and three equivalent Ni(5) atoms. In the fourth Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Yb(1); three Ni(4,4); and three equivalent Ni(5) atoms. In the fifth Ni site, Ni(4) is bonded to four equivalent Yb(1), two equivalent Ni(2), two equivalent Ni(3), and four equivalent Ni(4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra, corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra, edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra, edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra, faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra, and faces with eight equivalent Ni(4)Yb4Ni8 cuboctahedra. In the sixth Ni site, Ni(4) is bonded to four equivalent Yb(1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra; edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra; faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra; and faces with eight Ni(4,4)Yb4Ni8 cuboctahedra. In the seventh Ni site, Ni(5) is bonded to two equivalent Yb(1), three equivalent Yb(2), one Ni(1), one Ni(2), one Ni(3), and four equivalent Ni(5) atoms to form distorted NiYb5Ni7 cuboctahedra that share corners with two equivalent Ni(1)Yb6Ni6 cuboctahedra; corners with six Ni(4,4)Yb4Ni8 cuboctahedra; corners with nine equivalent Ni(5)Yb5Ni7 cuboctahedra; edges with four Ni(4,4)Yb4Ni8 cuboctahedra; edges with four equivalent Ni(5)Yb5Ni7 cuboctahedra;  a faceface with one Ni(4)Yb4Ni8 cuboctahedra; faces with three equivalent Ni(1)Yb6Ni6 cuboctahedra; and faces with ten equivalent Ni(5)Yb5Ni7 cuboctahedra. In the eighth Ni site, Ni(4) is bonded to four Yb(1,1); two equivalent Ni(2); two equivalent Ni(3); and four Ni(4,4) atoms to form NiYb4Ni8 cuboctahedra that share corners with four equivalent Ni(4)Yb4Ni8 cuboctahedra; corners with twelve equivalent Ni(5)Yb5Ni7 cuboctahedra; edges with two equivalent Ni(4)Yb4Ni8 cuboctahedra; edges with eight equivalent Ni(5)Yb5Ni7 cuboctahedra; faces with two equivalent Ni(5)Yb5Ni7 cuboctahedra; and faces with eight Ni(4,4)Yb4Ni8 cuboctahedra. is represented by the CIF card [CIF]
data_Yb2Ni7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.879
_cell_length_b   4.879
_cell_length_c   12.152
_cell_angle_alpha   78.419
_cell_angle_beta   78.419
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   243.709
_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
  Yb  Yb0  1  0.948  0.948  0.155  1.0
  Yb  Yb1  1  0.052  0.052  0.845  1.0
  Yb  Yb2  1  0.853  0.853  0.442  1.0
  Yb  Yb3  1  0.147  0.147  0.558  1.0
  Ni  Ni4  1  0.500  0.500  0.500  1.0
  Ni  Ni5  1  0.722  0.722  0.833  1.0
  Ni  Ni6  1  0.278  0.278  0.167  1.0
  Ni  Ni7  1  0.611  0.611  0.166  1.0
  Ni  Ni8  1  0.389  0.389  0.834  1.0
  Ni  Ni9  1  0.000  0.500  0.000  1.0
  Ni  Ni10  1  0.500  0.000  0.000  1.0
  Ni  Ni11  1  0.500  0.500  0.000  1.0
  Ni  Ni12  1  0.388  0.388  0.332  1.0
  Ni  Ni13  1  0.891  0.388  0.332  1.0
  Ni  Ni14  1  0.388  0.891  0.332  1.0
  Ni  Ni15  1  0.612  0.612  0.668  1.0
  Ni  Ni16  1  0.109  0.612  0.668  1.0
  Ni  Ni17  1  0.612  0.109  0.668  1.0
[/CIF]
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