The material described by ErNiSn2 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 14-coordinate geometry to one Ni(2), two equivalent Ni(3), three equivalent Ni(1), one Sn(6), two equivalent Sn(1), two equivalent Sn(4), and three equivalent Sn(3) atoms. In the second Er site, Er(2) is bonded in a 11-coordinate geometry to one Ni(3), two equivalent Ni(1), one Sn(1), one Sn(2), one Sn(3), two equivalent Sn(4), two equivalent Sn(5), and two equivalent Sn(6) atoms. In the third Er site, Er(3) is bonded in a 13-coordinate geometry to two equivalent Ni(2), two equivalent Ni(3), one Sn(1), one Sn(6), two equivalent Sn(4), two equivalent Sn(5), and three equivalent Sn(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 10-coordinate geometry to two equivalent Er(2), three equivalent Er(1), one Sn(4), one Sn(5), and three equivalent Sn(3) atoms. In the second Ni site, Ni(2) is bonded in a 7-coordinate geometry to one Er(1), two equivalent Er(3), one Sn(4), one Sn(5), one Sn(6), and two equivalent Sn(1) atoms. In the third Ni site, Ni(3) is bonded in a 10-coordinate geometry to one Er(2), two equivalent Er(1), two equivalent Er(3), one Sn(1), one Sn(2), one Sn(4), and two equivalent Sn(6) atoms. There are six inequivalent Sn sites. In the first Sn site, Sn(3) is bonded in a 8-coordinate geometry to one Er(2), three equivalent Er(1), three equivalent Ni(1), and one Sn(1) atom. In the second Sn site, Sn(4) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Er(3), one Ni(1), one Ni(2), and one Ni(3) atom. In the third Sn site, Sn(5) is bonded in a 6-coordinate geometry to two equivalent Er(2), two equivalent Er(3), one Ni(1), and one Ni(2) atom. In the fourth Sn site, Sn(6) is bonded in a 6-coordinate geometry to one Er(1), one Er(3), two equivalent Er(2), one Ni(2), and two equivalent Ni(3) atoms. In the fifth Sn site, Sn(1) is bonded in a 8-coordinate geometry to one Er(2), one Er(3), two equivalent Er(1), one Ni(3), two equivalent Ni(2), and one Sn(3) atom. In the sixth Sn site, Sn(2) is bonded in a 2-coordinate geometry to one Er(2), three equivalent Er(3), and one Ni(3) atom. is represented by the CIF file [CIF]
data_ErNiSn2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.419
_cell_length_b   14.583
_cell_length_c   16.072
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1035.743
_cell_formula_units_Z   12
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  0.250  0.973  0.349  1.0
  Er  Er1  1  0.250  0.527  0.849  1.0
  Er  Er2  1  0.750  0.027  0.651  1.0
  Er  Er3  1  0.750  0.473  0.151  1.0
  Er  Er4  1  0.250  0.276  0.869  1.0
  Er  Er5  1  0.250  0.224  0.369  1.0
  Er  Er6  1  0.750  0.724  0.131  1.0
  Er  Er7  1  0.750  0.776  0.631  1.0
  Er  Er8  1  0.250  0.397  0.645  1.0
  Er  Er9  1  0.250  0.103  0.145  1.0
  Er  Er10  1  0.750  0.603  0.355  1.0
  Er  Er11  1  0.750  0.897  0.855  1.0
  Ni  Ni12  1  0.250  0.606  0.055  1.0
  Ni  Ni13  1  0.250  0.894  0.555  1.0
  Ni  Ni14  1  0.750  0.394  0.945  1.0
  Ni  Ni15  1  0.750  0.106  0.445  1.0
  Ni  Ni16  1  0.250  0.744  0.310  1.0
  Ni  Ni17  1  0.250  0.756  0.810  1.0
  Ni  Ni18  1  0.750  0.256  0.690  1.0
  Ni  Ni19  1  0.750  0.244  0.190  1.0
  Ni  Ni20  1  0.250  0.049  0.799  1.0
  Ni  Ni21  1  0.250  0.451  0.299  1.0
  Ni  Ni22  1  0.750  0.951  0.201  1.0
  Ni  Ni23  1  0.750  0.549  0.701  1.0
  Sn  Sn24  1  0.250  0.177  0.681  1.0
  Sn  Sn25  1  0.250  0.323  0.181  1.0
  Sn  Sn26  1  0.750  0.823  0.319  1.0
  Sn  Sn27  1  0.750  0.677  0.819  1.0
  Sn  Sn28  1  0.250  0.054  0.957  1.0
  Sn  Sn29  1  0.250  0.446  0.457  1.0
  Sn  Sn30  1  0.750  0.946  0.043  1.0
  Sn  Sn31  1  0.750  0.554  0.543  1.0
  Sn  Sn32  1  0.250  0.079  0.518  1.0
  Sn  Sn33  1  0.250  0.421  0.018  1.0
  Sn  Sn34  1  0.750  0.921  0.482  1.0
  Sn  Sn35  1  0.750  0.579  0.982  1.0
  Sn  Sn36  1  0.250  0.603  0.217  1.0
  Sn  Sn37  1  0.250  0.897  0.717  1.0
  Sn  Sn38  1  0.750  0.397  0.783  1.0
  Sn  Sn39  1  0.750  0.103  0.283  1.0
  Sn  Sn40  1  0.250  0.734  0.473  1.0
  Sn  Sn41  1  0.250  0.766  0.973  1.0
  Sn  Sn42  1  0.750  0.266  0.527  1.0
  Sn  Sn43  1  0.750  0.234  0.027  1.0
  Sn  Sn44  1  0.250  0.868  0.176  1.0
  Sn  Sn45  1  0.250  0.632  0.676  1.0
  Sn  Sn46  1  0.750  0.132  0.824  1.0
  Sn  Sn47  1  0.750  0.368  0.324  1.0
[/CIF]
.
The material described by ErNiSn2 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 14-coordinate geometry to one Ni(2), two equivalent Ni(3), three equivalent Ni(1), one Sn(6), two equivalent Sn(1), two equivalent Sn(4), and three equivalent Sn(3) atoms. In the second Er site, Er(2) is bonded in a 11-coordinate geometry to one Ni(3), two equivalent Ni(1), one Sn(1), one Sn(2), one Sn(3), two equivalent Sn(4), two equivalent Sn(5), and two equivalent Sn(6) atoms. In the third Er site, Er(3) is bonded in a 13-coordinate geometry to two equivalent Ni(2), two equivalent Ni(3), one Sn(1), one Sn(6), two equivalent Sn(4), two equivalent Sn(5), and three equivalent Sn(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 10-coordinate geometry to two equivalent Er(2), three equivalent Er(1), one Sn(4), one Sn(5), and three equivalent Sn(3) atoms. In the second Ni site, Ni(2) is bonded in a 7-coordinate geometry to one Er(1), two equivalent Er(3), one Sn(4), one Sn(5), one Sn(6), and two equivalent Sn(1) atoms. In the third Ni site, Ni(3) is bonded in a 10-coordinate geometry to one Er(2), two equivalent Er(1), two equivalent Er(3), one Sn(1), one Sn(2), one Sn(4), and two equivalent Sn(6) atoms. There are six inequivalent Sn sites. In the first Sn site, Sn(3) is bonded in a 8-coordinate geometry to one Er(2), three equivalent Er(1), three equivalent Ni(1), and one Sn(1) atom. In the second Sn site, Sn(4) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Er(3), one Ni(1), one Ni(2), and one Ni(3) atom. In the third Sn site, Sn(5) is bonded in a 6-coordinate geometry to two equivalent Er(2), two equivalent Er(3), one Ni(1), and one Ni(2) atom. In the fourth Sn site, Sn(6) is bonded in a 6-coordinate geometry to one Er(1), one Er(3), two equivalent Er(2), one Ni(2), and two equivalent Ni(3) atoms. In the fifth Sn site, Sn(1) is bonded in a 8-coordinate geometry to one Er(2), one Er(3), two equivalent Er(1), one Ni(3), two equivalent Ni(2), and one Sn(3) atom. In the sixth Sn site, Sn(2) is bonded in a 2-coordinate geometry to one Er(2), three equivalent Er(3), and one Ni(3) atom. is represented by the CIF file [CIF]
data_ErNiSn2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.419
_cell_length_b   14.583
_cell_length_c   16.072
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1035.743
_cell_formula_units_Z   12
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  0.250  0.973  0.349  1.0
  Er  Er1  1  0.250  0.527  0.849  1.0
  Er  Er2  1  0.750  0.027  0.651  1.0
  Er  Er3  1  0.750  0.473  0.151  1.0
  Er  Er4  1  0.250  0.276  0.869  1.0
  Er  Er5  1  0.250  0.224  0.369  1.0
  Er  Er6  1  0.750  0.724  0.131  1.0
  Er  Er7  1  0.750  0.776  0.631  1.0
  Er  Er8  1  0.250  0.397  0.645  1.0
  Er  Er9  1  0.250  0.103  0.145  1.0
  Er  Er10  1  0.750  0.603  0.355  1.0
  Er  Er11  1  0.750  0.897  0.855  1.0
  Ni  Ni12  1  0.250  0.606  0.055  1.0
  Ni  Ni13  1  0.250  0.894  0.555  1.0
  Ni  Ni14  1  0.750  0.394  0.945  1.0
  Ni  Ni15  1  0.750  0.106  0.445  1.0
  Ni  Ni16  1  0.250  0.744  0.310  1.0
  Ni  Ni17  1  0.250  0.756  0.810  1.0
  Ni  Ni18  1  0.750  0.256  0.690  1.0
  Ni  Ni19  1  0.750  0.244  0.190  1.0
  Ni  Ni20  1  0.250  0.049  0.799  1.0
  Ni  Ni21  1  0.250  0.451  0.299  1.0
  Ni  Ni22  1  0.750  0.951  0.201  1.0
  Ni  Ni23  1  0.750  0.549  0.701  1.0
  Sn  Sn24  1  0.250  0.177  0.681  1.0
  Sn  Sn25  1  0.250  0.323  0.181  1.0
  Sn  Sn26  1  0.750  0.823  0.319  1.0
  Sn  Sn27  1  0.750  0.677  0.819  1.0
  Sn  Sn28  1  0.250  0.054  0.957  1.0
  Sn  Sn29  1  0.250  0.446  0.457  1.0
  Sn  Sn30  1  0.750  0.946  0.043  1.0
  Sn  Sn31  1  0.750  0.554  0.543  1.0
  Sn  Sn32  1  0.250  0.079  0.518  1.0
  Sn  Sn33  1  0.250  0.421  0.018  1.0
  Sn  Sn34  1  0.750  0.921  0.482  1.0
  Sn  Sn35  1  0.750  0.579  0.982  1.0
  Sn  Sn36  1  0.250  0.603  0.217  1.0
  Sn  Sn37  1  0.250  0.897  0.717  1.0
  Sn  Sn38  1  0.750  0.397  0.783  1.0
  Sn  Sn39  1  0.750  0.103  0.283  1.0
  Sn  Sn40  1  0.250  0.734  0.473  1.0
  Sn  Sn41  1  0.250  0.766  0.973  1.0
  Sn  Sn42  1  0.750  0.266  0.527  1.0
  Sn  Sn43  1  0.750  0.234  0.027  1.0
  Sn  Sn44  1  0.250  0.868  0.176  1.0
  Sn  Sn45  1  0.250  0.632  0.676  1.0
  Sn  Sn46  1  0.750  0.132  0.824  1.0
  Sn  Sn47  1  0.750  0.368  0.324  1.0
[/CIF]
.