The compound described by Er2Co17 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 18-coordinate geometry to six equivalent Co(2) and twelve equivalent Co(3) atoms. In the second Er site, Er(2) is bonded in a 20-coordinate geometry to two equivalent Co(4), six equivalent Co(1), six equivalent Co(2), and six equivalent Co(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(4) is bonded in a 14-coordinate geometry to one Er(2), one Co(4), three equivalent Co(1), three equivalent Co(3), and six equivalent Co(2) atoms. In the second Co site, Co(1) is bonded to two equivalent Er(2), two equivalent Co(4), four equivalent Co(2), and four equivalent Co(3) atoms to form CoEr2Co10 cuboctahedra that share corners with four equivalent Co(1)Er2Co10 cuboctahedra, corners with ten equivalent Co(3)Er3Co9 cuboctahedra, edges with six equivalent Co(3)Er3Co9 cuboctahedra, faces with four equivalent Co(3)Er3Co9 cuboctahedra, and faces with six equivalent Co(1)Er2Co10 cuboctahedra. In the third Co site, Co(2) is bonded in a 12-coordinate geometry to one Er(1), one Er(2), two equivalent Co(1), two equivalent Co(2), two equivalent Co(4), and four equivalent Co(3) atoms. In the fourth Co site, Co(3) is bonded to one Er(2), two equivalent Er(1), one Co(4), two equivalent Co(1), two equivalent Co(3), and four equivalent Co(2) atoms to form distorted CoEr3Co9 cuboctahedra that share corners with five equivalent Co(1)Er2Co10 cuboctahedra, corners with ten equivalent Co(3)Er3Co9 cuboctahedra, edges with three equivalent Co(1)Er2Co10 cuboctahedra, edges with five equivalent Co(3)Er3Co9 cuboctahedra, faces with two equivalent Co(1)Er2Co10 cuboctahedra, and faces with eight equivalent Co(3)Er3Co9 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2Co17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.221
_cell_length_b   8.221
_cell_length_c   8.034
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.001
_symmetry_Int_Tables_number   1
_cell_volume   470.196
_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
  Er  Er0  1  1.000  1.000  0.250  1.0
  Er  Er1  1  0.000  0.000  0.750  1.0
  Er  Er2  1  0.333  0.667  0.750  1.0
  Er  Er3  1  0.667  0.333  0.250  1.0
  Co  Co4  1  0.500  0.000  0.000  1.0
  Co  Co5  1  0.500  0.500  0.500  1.0
  Co  Co6  1  0.000  0.500  0.500  1.0
  Co  Co7  1  1.000  0.500  0.000  1.0
  Co  Co8  1  0.500  0.500  0.000  1.0
  Co  Co9  1  0.500  1.000  0.500  1.0
  Co  Co10  1  0.330  0.957  0.250  1.0
  Co  Co11  1  0.373  0.330  0.750  1.0
  Co  Co12  1  0.957  0.627  0.750  1.0
  Co  Co13  1  0.043  0.373  0.250  1.0
  Co  Co14  1  0.627  0.670  0.250  1.0
  Co  Co15  1  0.373  0.043  0.750  1.0
  Co  Co16  1  0.670  0.627  0.750  1.0
  Co  Co17  1  0.670  0.043  0.750  1.0
  Co  Co18  1  0.957  0.330  0.750  1.0
  Co  Co19  1  0.043  0.670  0.250  1.0
  Co  Co20  1  0.627  0.957  0.250  1.0
  Co  Co21  1  0.330  0.373  0.250  1.0
  Co  Co22  1  0.166  0.331  0.983  1.0
  Co  Co23  1  0.835  0.166  0.483  1.0
  Co  Co24  1  0.331  0.166  0.483  1.0
  Co  Co25  1  0.669  0.834  0.983  1.0
  Co  Co26  1  0.166  0.834  0.983  1.0
  Co  Co27  1  0.834  0.669  0.017  1.0
  Co  Co28  1  0.835  0.166  0.017  1.0
  Co  Co29  1  0.834  0.669  0.483  1.0
  Co  Co30  1  0.331  0.166  0.017  1.0
  Co  Co31  1  0.669  0.834  0.517  1.0
  Co  Co32  1  0.166  0.331  0.517  1.0
  Co  Co33  1  0.166  0.834  0.517  1.0
  Co  Co34  1  0.333  0.667  0.108  1.0
  Co  Co35  1  0.667  0.333  0.608  1.0
  Co  Co36  1  0.667  0.333  0.892  1.0
  Co  Co37  1  0.333  0.667  0.392  1.0
[/CIF]
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The compound described by Er2Co17 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 18-coordinate geometry to six equivalent Co(2) and twelve equivalent Co(3) atoms. In the second Er site, Er(2) is bonded in a 20-coordinate geometry to two equivalent Co(4), six equivalent Co(1), six equivalent Co(2), and six equivalent Co(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(4) is bonded in a 14-coordinate geometry to one Er(2), one Co(4), three equivalent Co(1), three equivalent Co(3), and six equivalent Co(2) atoms. In the second Co site, Co(1) is bonded to two equivalent Er(2), two equivalent Co(4), four equivalent Co(2), and four equivalent Co(3) atoms to form CoEr2Co10 cuboctahedra that share corners with four equivalent Co(1)Er2Co10 cuboctahedra, corners with ten equivalent Co(3)Er3Co9 cuboctahedra, edges with six equivalent Co(3)Er3Co9 cuboctahedra, faces with four equivalent Co(3)Er3Co9 cuboctahedra, and faces with six equivalent Co(1)Er2Co10 cuboctahedra. In the third Co site, Co(2) is bonded in a 12-coordinate geometry to one Er(1), one Er(2), two equivalent Co(1), two equivalent Co(2), two equivalent Co(4), and four equivalent Co(3) atoms. In the fourth Co site, Co(3) is bonded to one Er(2), two equivalent Er(1), one Co(4), two equivalent Co(1), two equivalent Co(3), and four equivalent Co(2) atoms to form distorted CoEr3Co9 cuboctahedra that share corners with five equivalent Co(1)Er2Co10 cuboctahedra, corners with ten equivalent Co(3)Er3Co9 cuboctahedra, edges with three equivalent Co(1)Er2Co10 cuboctahedra, edges with five equivalent Co(3)Er3Co9 cuboctahedra, faces with two equivalent Co(1)Er2Co10 cuboctahedra, and faces with eight equivalent Co(3)Er3Co9 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2Co17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.221
_cell_length_b   8.221
_cell_length_c   8.034
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.001
_symmetry_Int_Tables_number   1
_cell_volume   470.196
_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
  Er  Er0  1  1.000  1.000  0.250  1.0
  Er  Er1  1  0.000  0.000  0.750  1.0
  Er  Er2  1  0.333  0.667  0.750  1.0
  Er  Er3  1  0.667  0.333  0.250  1.0
  Co  Co4  1  0.500  0.000  0.000  1.0
  Co  Co5  1  0.500  0.500  0.500  1.0
  Co  Co6  1  0.000  0.500  0.500  1.0
  Co  Co7  1  1.000  0.500  0.000  1.0
  Co  Co8  1  0.500  0.500  0.000  1.0
  Co  Co9  1  0.500  1.000  0.500  1.0
  Co  Co10  1  0.330  0.957  0.250  1.0
  Co  Co11  1  0.373  0.330  0.750  1.0
  Co  Co12  1  0.957  0.627  0.750  1.0
  Co  Co13  1  0.043  0.373  0.250  1.0
  Co  Co14  1  0.627  0.670  0.250  1.0
  Co  Co15  1  0.373  0.043  0.750  1.0
  Co  Co16  1  0.670  0.627  0.750  1.0
  Co  Co17  1  0.670  0.043  0.750  1.0
  Co  Co18  1  0.957  0.330  0.750  1.0
  Co  Co19  1  0.043  0.670  0.250  1.0
  Co  Co20  1  0.627  0.957  0.250  1.0
  Co  Co21  1  0.330  0.373  0.250  1.0
  Co  Co22  1  0.166  0.331  0.983  1.0
  Co  Co23  1  0.835  0.166  0.483  1.0
  Co  Co24  1  0.331  0.166  0.483  1.0
  Co  Co25  1  0.669  0.834  0.983  1.0
  Co  Co26  1  0.166  0.834  0.983  1.0
  Co  Co27  1  0.834  0.669  0.017  1.0
  Co  Co28  1  0.835  0.166  0.017  1.0
  Co  Co29  1  0.834  0.669  0.483  1.0
  Co  Co30  1  0.331  0.166  0.017  1.0
  Co  Co31  1  0.669  0.834  0.517  1.0
  Co  Co32  1  0.166  0.331  0.517  1.0
  Co  Co33  1  0.166  0.834  0.517  1.0
  Co  Co34  1  0.333  0.667  0.108  1.0
  Co  Co35  1  0.667  0.333  0.608  1.0
  Co  Co36  1  0.667  0.333  0.892  1.0
  Co  Co37  1  0.333  0.667  0.392  1.0
[/CIF]
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