The material described by ErNi7B3 crystallizes in the tetragonal I4_1/amd space group. Er(1) is bonded in a 18-coordinate geometry to two equivalent Ni(4), four equivalent Ni(1), four equivalent Ni(2), four equivalent Ni(3), and four equivalent B(1) atoms. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 6-coordinate geometry to two equivalent Er(1), two equivalent B(1), and two equivalent B(2) atoms. In the second Ni site, Ni(2) is bonded in a 5-coordinate geometry to two equivalent Er(1), one B(2), and two equivalent B(1) atoms. In the third Ni site, Ni(3) is bonded in a 3-coordinate geometry to two equivalent Er(1) and two equivalent B(1) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted square co-planar geometry to two equivalent Er(1), two equivalent B(1), and two equivalent B(2) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 7-coordinate geometry to two equivalent Er(1), one Ni(4), two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Ni(2), two equivalent Ni(4), four equivalent Ni(1), and one B(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErNi7B3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.468
_cell_length_b   9.468
_cell_length_c   9.468
_cell_angle_alpha   132.450
_cell_angle_beta   132.450
_cell_angle_gamma   69.520
_symmetry_Int_Tables_number   1
_cell_volume   453.347
_cell_formula_units_Z   4
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  0.216  0.216  0.000  1.0
  Er  Er1  1  0.966  0.466  0.500  1.0
  Er  Er2  1  0.534  0.034  0.500  1.0
  Er  Er3  1  0.784  0.784  0.000  1.0
  Ni  Ni4  1  0.312  0.312  0.625  1.0
  Ni  Ni5  1  0.312  0.688  0.000  1.0
  Ni  Ni6  1  0.688  0.312  0.000  1.0
  Ni  Ni7  1  0.438  0.938  0.875  1.0
  Ni  Ni8  1  0.181  0.893  0.288  1.0
  Ni  Ni9  1  0.643  0.855  0.212  1.0
  Ni  Ni10  1  0.643  0.431  0.788  1.0
  Ni  Ni11  1  0.062  0.562  0.125  1.0
  Ni  Ni12  1  0.145  0.357  0.788  1.0
  Ni  Ni13  1  0.107  0.395  0.288  1.0
  Ni  Ni14  1  0.107  0.819  0.712  1.0
  Ni  Ni15  1  0.605  0.893  0.712  1.0
  Ni  Ni16  1  0.219  0.056  0.162  1.0
  Ni  Ni17  1  0.806  0.144  0.338  1.0
  Ni  Ni18  1  0.806  0.469  0.662  1.0
  Ni  Ni19  1  0.531  0.194  0.338  1.0
  Ni  Ni20  1  0.856  0.194  0.662  1.0
  Ni  Ni21  1  0.944  0.106  0.162  1.0
  Ni  Ni22  1  0.944  0.781  0.838  1.0
  Ni  Ni23  1  0.894  0.056  0.838  1.0
  Ni  Ni24  1  0.438  0.562  0.500  1.0
  Ni  Ni25  1  0.688  0.688  0.375  1.0
  Ni  Ni26  1  0.375  0.625  0.750  1.0
  Ni  Ni27  1  0.375  0.125  0.750  1.0
  Ni  Ni28  1  0.375  0.625  0.250  1.0
  Ni  Ni29  1  0.875  0.625  0.250  1.0
  Ni  Ni30  1  0.569  0.357  0.212  1.0
  Ni  Ni31  1  0.062  0.938  0.500  1.0
  B  B32  1  0.375  0.915  0.040  1.0
  B  B33  1  0.665  0.125  0.040  1.0
  B  B34  1  0.085  0.625  0.960  1.0
  B  B35  1  0.875  0.335  0.960  1.0
  B  B36  1  0.665  0.625  0.540  1.0
  B  B37  1  0.875  0.915  0.540  1.0
  B  B38  1  0.559  0.559  0.000  1.0
  B  B39  1  0.309  0.809  0.500  1.0
  B  B40  1  0.191  0.691  0.500  1.0
  B  B41  1  0.441  0.441  0.000  1.0
  B  B42  1  0.375  0.335  0.460  1.0
  B  B43  1  0.085  0.125  0.460  1.0
[/CIF]
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The material described by ErNi7B3 crystallizes in the tetragonal I4_1/amd space group. Er(1) is bonded in a 18-coordinate geometry to two equivalent Ni(4), four equivalent Ni(1), four equivalent Ni(2), four equivalent Ni(3), and four equivalent B(1) atoms. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 6-coordinate geometry to two equivalent Er(1), two equivalent B(1), and two equivalent B(2) atoms. In the second Ni site, Ni(2) is bonded in a 5-coordinate geometry to two equivalent Er(1), one B(2), and two equivalent B(1) atoms. In the third Ni site, Ni(3) is bonded in a 3-coordinate geometry to two equivalent Er(1) and two equivalent B(1) atoms. In the fourth Ni site, Ni(4) is bonded in a distorted square co-planar geometry to two equivalent Er(1), two equivalent B(1), and two equivalent B(2) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 7-coordinate geometry to two equivalent Er(1), one Ni(4), two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Ni(2), two equivalent Ni(4), four equivalent Ni(1), and one B(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErNi7B3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.468
_cell_length_b   9.468
_cell_length_c   9.468
_cell_angle_alpha   132.450
_cell_angle_beta   132.450
_cell_angle_gamma   69.520
_symmetry_Int_Tables_number   1
_cell_volume   453.347
_cell_formula_units_Z   4
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  0.216  0.216  0.000  1.0
  Er  Er1  1  0.966  0.466  0.500  1.0
  Er  Er2  1  0.534  0.034  0.500  1.0
  Er  Er3  1  0.784  0.784  0.000  1.0
  Ni  Ni4  1  0.312  0.312  0.625  1.0
  Ni  Ni5  1  0.312  0.688  0.000  1.0
  Ni  Ni6  1  0.688  0.312  0.000  1.0
  Ni  Ni7  1  0.438  0.938  0.875  1.0
  Ni  Ni8  1  0.181  0.893  0.288  1.0
  Ni  Ni9  1  0.643  0.855  0.212  1.0
  Ni  Ni10  1  0.643  0.431  0.788  1.0
  Ni  Ni11  1  0.062  0.562  0.125  1.0
  Ni  Ni12  1  0.145  0.357  0.788  1.0
  Ni  Ni13  1  0.107  0.395  0.288  1.0
  Ni  Ni14  1  0.107  0.819  0.712  1.0
  Ni  Ni15  1  0.605  0.893  0.712  1.0
  Ni  Ni16  1  0.219  0.056  0.162  1.0
  Ni  Ni17  1  0.806  0.144  0.338  1.0
  Ni  Ni18  1  0.806  0.469  0.662  1.0
  Ni  Ni19  1  0.531  0.194  0.338  1.0
  Ni  Ni20  1  0.856  0.194  0.662  1.0
  Ni  Ni21  1  0.944  0.106  0.162  1.0
  Ni  Ni22  1  0.944  0.781  0.838  1.0
  Ni  Ni23  1  0.894  0.056  0.838  1.0
  Ni  Ni24  1  0.438  0.562  0.500  1.0
  Ni  Ni25  1  0.688  0.688  0.375  1.0
  Ni  Ni26  1  0.375  0.625  0.750  1.0
  Ni  Ni27  1  0.375  0.125  0.750  1.0
  Ni  Ni28  1  0.375  0.625  0.250  1.0
  Ni  Ni29  1  0.875  0.625  0.250  1.0
  Ni  Ni30  1  0.569  0.357  0.212  1.0
  Ni  Ni31  1  0.062  0.938  0.500  1.0
  B  B32  1  0.375  0.915  0.040  1.0
  B  B33  1  0.665  0.125  0.040  1.0
  B  B34  1  0.085  0.625  0.960  1.0
  B  B35  1  0.875  0.335  0.960  1.0
  B  B36  1  0.665  0.625  0.540  1.0
  B  B37  1  0.875  0.915  0.540  1.0
  B  B38  1  0.559  0.559  0.000  1.0
  B  B39  1  0.309  0.809  0.500  1.0
  B  B40  1  0.191  0.691  0.500  1.0
  B  B41  1  0.441  0.441  0.000  1.0
  B  B42  1  0.375  0.335  0.460  1.0
  B  B43  1  0.085  0.125  0.460  1.0
[/CIF]
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