The compound described by Er6Ni20P13 crystallizes in the hexagonal P-6 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 16-coordinate geometry to one Ni(1), one Ni(8), two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), two equivalent Ni(7), two equivalent P(2), and four equivalent P(1) atoms. In the second Er site, Er(2) is bonded in a 15-coordinate geometry to one Ni(6), two equivalent Ni(4), two equivalent Ni(5), two equivalent Ni(7), two equivalent Ni(8), two equivalent P(4), and four equivalent P(3) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one Er(1), one P(4), one P(5), and two equivalent P(2) atoms to form distorted NiErP4 tetrahedra that share  a cornercorner with one Ni(5)Er4P4 tetrahedra, corners with four equivalent Ni(1)ErP4 tetrahedra,  an edgeedge with one Ni(5)Er4P4 tetrahedra, edges with two equivalent Ni(7)Er4P4 tetrahedra, and faces with two equivalent Ni(6)Er3P4 tetrahedra. In the second Ni site, Ni(2) is bonded in a distorted trigonal planar geometry to six equivalent Er(1) and three equivalent P(1) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one P(2), two equivalent P(4), and two equivalent P(5) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to six equivalent Er(2) and three equivalent P(3) atoms. In the fifth Ni site, Ni(5) is bonded to two equivalent Er(1), two equivalent Er(2), one P(3), one P(4), and two equivalent P(1) atoms to form distorted NiEr4P4 tetrahedra that share  a cornercorner with one Ni(1)ErP4 tetrahedra, corners with two equivalent Ni(6)Er3P4 tetrahedra, corners with two equivalent Ni(5)Er4P4 tetrahedra, corners with four equivalent Ni(7)Er4P4 tetrahedra,  an edgeedge with one Ni(1)ErP4 tetrahedra, edges with two equivalent Ni(5)Er4P4 tetrahedra, faces with two equivalent Ni(6)Er3P4 tetrahedra, and faces with two equivalent Ni(7)Er4P4 tetrahedra. In the sixth Ni site, Ni(6) is bonded to one Er(2), two equivalent Er(1), one P(1), one P(2), and two equivalent P(4) atoms to form distorted NiEr3P4 tetrahedra that share corners with two equivalent Ni(5)Er4P4 tetrahedra, corners with three equivalent Ni(7)Er4P4 tetrahedra,  an edgeedge with one Ni(7)Er4P4 tetrahedra, edges with two equivalent Ni(6)Er3P4 tetrahedra,  a faceface with one Ni(7)Er4P4 tetrahedra, faces with two equivalent Ni(5)Er4P4 tetrahedra, and faces with two equivalent Ni(1)ErP4 tetrahedra. In the seventh Ni site, Ni(7) is bonded to two equivalent Er(1), two equivalent Er(2), one P(1), one P(2), and two equivalent P(3) atoms to form distorted NiEr4P4 tetrahedra that share corners with two equivalent Ni(7)Er4P4 tetrahedra, corners with three equivalent Ni(6)Er3P4 tetrahedra, corners with four equivalent Ni(5)Er4P4 tetrahedra,  an edgeedge with one Ni(6)Er3P4 tetrahedra, edges with two equivalent Ni(7)Er4P4 tetrahedra, edges with two equivalent Ni(1)ErP4 tetrahedra,  a faceface with one Ni(6)Er3P4 tetrahedra, and faces with two equivalent Ni(5)Er4P4 tetrahedra. In the eighth Ni site, Ni(8) is bonded in a 4-coordinate geometry to one Er(1), two equivalent Er(2), one P(3), one P(4), and two equivalent P(2) atoms. There are five inequivalent P sites. In the first P site, P(3) is bonded in a 9-coordinate geometry to four equivalent Er(2), one Ni(4), one Ni(5), one Ni(8), and two equivalent Ni(7) atoms. In the second P site, P(4) is bonded in a 9-coordinate geometry to two equivalent Er(2), one Ni(1), one Ni(5), one Ni(8), two equivalent Ni(3), and two equivalent Ni(6) atoms. In the third P site, P(5) is bonded in a 9-coordinate geometry to three equivalent Ni(1) and six equivalent Ni(3) atoms. In the fourth P site, P(1) is bonded in a 9-coordinate geometry to four equivalent Er(1), one Ni(2), one Ni(6), one Ni(7), and two equivalent Ni(5) atoms. In the fifth P site, P(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), one Ni(3), one Ni(6), one Ni(7), two equivalent Ni(1), and two equivalent Ni(8) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er6Ni20P13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.528
_cell_length_b   12.528
_cell_length_c   3.711
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.996
_symmetry_Int_Tables_number   1
_cell_volume   504.423
_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
  Er  Er0  1  0.529  0.811  0.000  1.0
  Er  Er1  1  0.282  0.471  0.000  1.0
  Er  Er2  1  0.189  0.718  0.000  1.0
  Er  Er3  1  0.811  0.282  0.500  1.0
  Er  Er4  1  0.471  0.189  0.500  1.0
  Er  Er5  1  0.718  0.529  0.500  1.0
  Ni  Ni6  1  0.804  0.908  0.000  1.0
  Ni  Ni7  1  0.104  0.196  0.000  1.0
  Ni  Ni8  1  0.092  0.896  0.000  1.0
  Ni  Ni9  1  0.333  0.667  0.500  1.0
  Ni  Ni10  1  0.927  0.078  0.500  1.0
  Ni  Ni11  1  0.151  0.073  0.500  1.0
  Ni  Ni12  1  0.922  0.849  0.500  1.0
  Ni  Ni13  1  0.667  0.333  0.000  1.0
  Ni  Ni14  1  0.562  0.583  0.000  1.0
  Ni  Ni15  1  0.021  0.438  0.000  1.0
  Ni  Ni16  1  0.417  0.979  0.000  1.0
  Ni  Ni17  1  0.682  0.753  0.500  1.0
  Ni  Ni18  1  0.071  0.318  0.500  1.0
  Ni  Ni19  1  0.247  0.929  0.500  1.0
  Ni  Ni20  1  0.979  0.566  0.500  1.0
  Ni  Ni21  1  0.587  0.021  0.500  1.0
  Ni  Ni22  1  0.434  0.413  0.500  1.0
  Ni  Ni23  1  0.759  0.079  0.000  1.0
  Ni  Ni24  1  0.320  0.241  0.000  1.0
  Ni  Ni25  1  0.921  0.680  0.000  1.0
  P  P26  1  0.476  0.613  0.500  1.0
  P  P27  1  0.137  0.524  0.500  1.0
  P  P28  1  0.387  0.863  0.500  1.0
  P  P29  1  0.720  0.952  0.500  1.0
  P  P30  1  0.232  0.280  0.500  1.0
  P  P31  1  0.048  0.768  0.500  1.0
  P  P32  1  0.862  0.477  0.000  1.0
  P  P33  1  0.615  0.138  0.000  1.0
  P  P34  1  0.523  0.385  0.000  1.0
  P  P35  1  0.952  0.235  0.000  1.0
  P  P36  1  0.284  0.048  0.000  1.0
  P  P37  1  0.765  0.716  0.000  1.0
  P  P38  1  0.000  0.000  0.000  1.0
[/CIF]
.
The compound described by Er6Ni20P13 crystallizes in the hexagonal P-6 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 16-coordinate geometry to one Ni(1), one Ni(8), two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), two equivalent Ni(7), two equivalent P(2), and four equivalent P(1) atoms. In the second Er site, Er(2) is bonded in a 15-coordinate geometry to one Ni(6), two equivalent Ni(4), two equivalent Ni(5), two equivalent Ni(7), two equivalent Ni(8), two equivalent P(4), and four equivalent P(3) atoms. There are eight inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one Er(1), one P(4), one P(5), and two equivalent P(2) atoms to form distorted NiErP4 tetrahedra that share  a cornercorner with one Ni(5)Er4P4 tetrahedra, corners with four equivalent Ni(1)ErP4 tetrahedra,  an edgeedge with one Ni(5)Er4P4 tetrahedra, edges with two equivalent Ni(7)Er4P4 tetrahedra, and faces with two equivalent Ni(6)Er3P4 tetrahedra. In the second Ni site, Ni(2) is bonded in a distorted trigonal planar geometry to six equivalent Er(1) and three equivalent P(1) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one P(2), two equivalent P(4), and two equivalent P(5) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted trigonal planar geometry to six equivalent Er(2) and three equivalent P(3) atoms. In the fifth Ni site, Ni(5) is bonded to two equivalent Er(1), two equivalent Er(2), one P(3), one P(4), and two equivalent P(1) atoms to form distorted NiEr4P4 tetrahedra that share  a cornercorner with one Ni(1)ErP4 tetrahedra, corners with two equivalent Ni(6)Er3P4 tetrahedra, corners with two equivalent Ni(5)Er4P4 tetrahedra, corners with four equivalent Ni(7)Er4P4 tetrahedra,  an edgeedge with one Ni(1)ErP4 tetrahedra, edges with two equivalent Ni(5)Er4P4 tetrahedra, faces with two equivalent Ni(6)Er3P4 tetrahedra, and faces with two equivalent Ni(7)Er4P4 tetrahedra. In the sixth Ni site, Ni(6) is bonded to one Er(2), two equivalent Er(1), one P(1), one P(2), and two equivalent P(4) atoms to form distorted NiEr3P4 tetrahedra that share corners with two equivalent Ni(5)Er4P4 tetrahedra, corners with three equivalent Ni(7)Er4P4 tetrahedra,  an edgeedge with one Ni(7)Er4P4 tetrahedra, edges with two equivalent Ni(6)Er3P4 tetrahedra,  a faceface with one Ni(7)Er4P4 tetrahedra, faces with two equivalent Ni(5)Er4P4 tetrahedra, and faces with two equivalent Ni(1)ErP4 tetrahedra. In the seventh Ni site, Ni(7) is bonded to two equivalent Er(1), two equivalent Er(2), one P(1), one P(2), and two equivalent P(3) atoms to form distorted NiEr4P4 tetrahedra that share corners with two equivalent Ni(7)Er4P4 tetrahedra, corners with three equivalent Ni(6)Er3P4 tetrahedra, corners with four equivalent Ni(5)Er4P4 tetrahedra,  an edgeedge with one Ni(6)Er3P4 tetrahedra, edges with two equivalent Ni(7)Er4P4 tetrahedra, edges with two equivalent Ni(1)ErP4 tetrahedra,  a faceface with one Ni(6)Er3P4 tetrahedra, and faces with two equivalent Ni(5)Er4P4 tetrahedra. In the eighth Ni site, Ni(8) is bonded in a 4-coordinate geometry to one Er(1), two equivalent Er(2), one P(3), one P(4), and two equivalent P(2) atoms. There are five inequivalent P sites. In the first P site, P(3) is bonded in a 9-coordinate geometry to four equivalent Er(2), one Ni(4), one Ni(5), one Ni(8), and two equivalent Ni(7) atoms. In the second P site, P(4) is bonded in a 9-coordinate geometry to two equivalent Er(2), one Ni(1), one Ni(5), one Ni(8), two equivalent Ni(3), and two equivalent Ni(6) atoms. In the third P site, P(5) is bonded in a 9-coordinate geometry to three equivalent Ni(1) and six equivalent Ni(3) atoms. In the fourth P site, P(1) is bonded in a 9-coordinate geometry to four equivalent Er(1), one Ni(2), one Ni(6), one Ni(7), and two equivalent Ni(5) atoms. In the fifth P site, P(2) is bonded in a 9-coordinate geometry to two equivalent Er(1), one Ni(3), one Ni(6), one Ni(7), two equivalent Ni(1), and two equivalent Ni(8) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er6Ni20P13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.528
_cell_length_b   12.528
_cell_length_c   3.711
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.996
_symmetry_Int_Tables_number   1
_cell_volume   504.423
_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
  Er  Er0  1  0.529  0.811  0.000  1.0
  Er  Er1  1  0.282  0.471  0.000  1.0
  Er  Er2  1  0.189  0.718  0.000  1.0
  Er  Er3  1  0.811  0.282  0.500  1.0
  Er  Er4  1  0.471  0.189  0.500  1.0
  Er  Er5  1  0.718  0.529  0.500  1.0
  Ni  Ni6  1  0.804  0.908  0.000  1.0
  Ni  Ni7  1  0.104  0.196  0.000  1.0
  Ni  Ni8  1  0.092  0.896  0.000  1.0
  Ni  Ni9  1  0.333  0.667  0.500  1.0
  Ni  Ni10  1  0.927  0.078  0.500  1.0
  Ni  Ni11  1  0.151  0.073  0.500  1.0
  Ni  Ni12  1  0.922  0.849  0.500  1.0
  Ni  Ni13  1  0.667  0.333  0.000  1.0
  Ni  Ni14  1  0.562  0.583  0.000  1.0
  Ni  Ni15  1  0.021  0.438  0.000  1.0
  Ni  Ni16  1  0.417  0.979  0.000  1.0
  Ni  Ni17  1  0.682  0.753  0.500  1.0
  Ni  Ni18  1  0.071  0.318  0.500  1.0
  Ni  Ni19  1  0.247  0.929  0.500  1.0
  Ni  Ni20  1  0.979  0.566  0.500  1.0
  Ni  Ni21  1  0.587  0.021  0.500  1.0
  Ni  Ni22  1  0.434  0.413  0.500  1.0
  Ni  Ni23  1  0.759  0.079  0.000  1.0
  Ni  Ni24  1  0.320  0.241  0.000  1.0
  Ni  Ni25  1  0.921  0.680  0.000  1.0
  P  P26  1  0.476  0.613  0.500  1.0
  P  P27  1  0.137  0.524  0.500  1.0
  P  P28  1  0.387  0.863  0.500  1.0
  P  P29  1  0.720  0.952  0.500  1.0
  P  P30  1  0.232  0.280  0.500  1.0
  P  P31  1  0.048  0.768  0.500  1.0
  P  P32  1  0.862  0.477  0.000  1.0
  P  P33  1  0.615  0.138  0.000  1.0
  P  P34  1  0.523  0.385  0.000  1.0
  P  P35  1  0.952  0.235  0.000  1.0
  P  P36  1  0.284  0.048  0.000  1.0
  P  P37  1  0.765  0.716  0.000  1.0
  P  P38  1  0.000  0.000  0.000  1.0
[/CIF]
.