The material described by ErFe2H3 crystallizes in the trigonal R-3m space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to three equivalent Fe(2), three equivalent H(1), and three equivalent H(2) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one Fe(1), two equivalent Fe(2), one H(1), one H(2), and four equivalent H(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(4) is bonded in a square co-planar geometry to one Fe(1), one Fe(2), two equivalent H(1), and two equivalent H(3) atoms. In the second Fe site, Fe(1) is bonded to six equivalent Er(2) and six equivalent Fe(4) atoms to form FeEr6Fe6 cuboctahedra that share corners with six equivalent Fe(2)Er6Fe6 cuboctahedra, corners with six equivalent H(1)Er2Fe2 trigonal pyramids, corners with six equivalent H(2)Er2Fe2 trigonal pyramids, edges with six equivalent Fe(2)Er6Fe6 cuboctahedra, edges with six equivalent H(1)Er2Fe2 trigonal pyramids, and faces with twelve equivalent H(3)Er2Fe2 tetrahedra. In the third Fe site, Fe(2) is bonded to two equivalent Er(1), four equivalent Er(2), two equivalent Fe(4), and four equivalent Fe(3) atoms to form FeEr6Fe6 cuboctahedra that share corners with two equivalent Fe(1)Er6Fe6 cuboctahedra, corners with four equivalent Fe(2)Er6Fe6 cuboctahedra, corners with eight equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(1)Er2Fe2 trigonal pyramids, corners with two equivalent H(2)Er2Fe2 trigonal pyramids, edges with two equivalent Fe(1)Er6Fe6 cuboctahedra, edges with four equivalent Fe(2)Er6Fe6 cuboctahedra, edges with four equivalent H(3)Er2Fe2 tetrahedra, edges with two equivalent H(2)Er2Fe2 trigonal pyramids, faces with four equivalent H(3)Er2Fe2 tetrahedra, faces with four equivalent H(1)Er2Fe2 trigonal pyramids, and faces with four equivalent H(2)Er2Fe2 trigonal pyramids. In the fourth Fe site, Fe(3) is bonded in a square co-planar geometry to two equivalent Fe(2), two equivalent H(2), and two equivalent H(3) atoms. There are three inequivalent H sites. In the first H site, H(1) is bonded to one Er(1), one Er(2), and two equivalent Fe(4) atoms to form distorted HEr2Fe2 trigonal pyramids that share  a cornercorner with one Fe(1)Er6Fe6 cuboctahedra,  a cornercorner with one Fe(2)Er6Fe6 cuboctahedra, corners with eight equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(2)Er2Fe2 trigonal pyramids,  an edgeedge with one Fe(1)Er6Fe6 cuboctahedra,  an edgeedge with one H(2)Er2Fe2 trigonal pyramid, edges with two equivalent H(1)Er2Fe2 trigonal pyramids, and faces with two equivalent Fe(2)Er6Fe6 cuboctahedra. In the second H site, H(2) is bonded to one Er(1), one Er(2), and two equivalent Fe(3) atoms to form distorted HEr2Fe2 trigonal pyramids that share  a cornercorner with one Fe(1)Er6Fe6 cuboctahedra,  a cornercorner with one Fe(2)Er6Fe6 cuboctahedra, corners with four equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(1)Er2Fe2 trigonal pyramids, corners with four equivalent H(2)Er2Fe2 trigonal pyramids,  an edgeedge with one Fe(2)Er6Fe6 cuboctahedra, edges with two equivalent H(3)Er2Fe2 tetrahedra,  an edgeedge with one H(1)Er2Fe2 trigonal pyramid, and faces with two equivalent Fe(2)Er6Fe6 cuboctahedra. In the third H site, H(3) is bonded to two equivalent Er(2), one Fe(3), and one Fe(4) atom to form distorted HEr2Fe2 tetrahedra that share corners with two equivalent Fe(2)Er6Fe6 cuboctahedra, corners with four equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(2)Er2Fe2 trigonal pyramids, corners with four equivalent H(1)Er2Fe2 trigonal pyramids,  an edgeedge with one Fe(2)Er6Fe6 cuboctahedra, edges with two equivalent H(3)Er2Fe2 tetrahedra,  an edgeedge with one H(2)Er2Fe2 trigonal pyramid,  a faceface with one Fe(1)Er6Fe6 cuboctahedra, and  a faceface with one Fe(2)Er6Fe6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErFe2H3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.270
_cell_length_b   5.270
_cell_length_c   5.270
_cell_angle_alpha   63.945
_cell_angle_beta   63.945
_cell_angle_gamma   63.945
_symmetry_Int_Tables_number   1
_cell_volume   112.466
_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  0.133  0.133  0.133  1.0
  Er  Er1  1  0.867  0.867  0.867  1.0
  Fe  Fe2  1  0.500  0.500  0.500  1.0
  Fe  Fe3  1  0.500  1.000  0.500  1.0
  Fe  Fe4  1  0.500  0.500  0.000  1.0
  Fe  Fe5  1  0.000  0.500  0.500  1.0
  H  H6  1  0.138  0.546  0.138  1.0
  H  H7  1  0.138  0.138  0.546  1.0
  H  H8  1  0.546  0.138  0.138  1.0
  H  H9  1  0.862  0.454  0.862  1.0
  H  H10  1  0.862  0.862  0.454  1.0
  H  H11  1  0.454  0.862  0.862  1.0
[/CIF]
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The material described by ErFe2H3 crystallizes in the trigonal R-3m space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to three equivalent Fe(2), three equivalent H(1), and three equivalent H(2) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one Fe(1), two equivalent Fe(2), one H(1), one H(2), and four equivalent H(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(4) is bonded in a square co-planar geometry to one Fe(1), one Fe(2), two equivalent H(1), and two equivalent H(3) atoms. In the second Fe site, Fe(1) is bonded to six equivalent Er(2) and six equivalent Fe(4) atoms to form FeEr6Fe6 cuboctahedra that share corners with six equivalent Fe(2)Er6Fe6 cuboctahedra, corners with six equivalent H(1)Er2Fe2 trigonal pyramids, corners with six equivalent H(2)Er2Fe2 trigonal pyramids, edges with six equivalent Fe(2)Er6Fe6 cuboctahedra, edges with six equivalent H(1)Er2Fe2 trigonal pyramids, and faces with twelve equivalent H(3)Er2Fe2 tetrahedra. In the third Fe site, Fe(2) is bonded to two equivalent Er(1), four equivalent Er(2), two equivalent Fe(4), and four equivalent Fe(3) atoms to form FeEr6Fe6 cuboctahedra that share corners with two equivalent Fe(1)Er6Fe6 cuboctahedra, corners with four equivalent Fe(2)Er6Fe6 cuboctahedra, corners with eight equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(1)Er2Fe2 trigonal pyramids, corners with two equivalent H(2)Er2Fe2 trigonal pyramids, edges with two equivalent Fe(1)Er6Fe6 cuboctahedra, edges with four equivalent Fe(2)Er6Fe6 cuboctahedra, edges with four equivalent H(3)Er2Fe2 tetrahedra, edges with two equivalent H(2)Er2Fe2 trigonal pyramids, faces with four equivalent H(3)Er2Fe2 tetrahedra, faces with four equivalent H(1)Er2Fe2 trigonal pyramids, and faces with four equivalent H(2)Er2Fe2 trigonal pyramids. In the fourth Fe site, Fe(3) is bonded in a square co-planar geometry to two equivalent Fe(2), two equivalent H(2), and two equivalent H(3) atoms. There are three inequivalent H sites. In the first H site, H(1) is bonded to one Er(1), one Er(2), and two equivalent Fe(4) atoms to form distorted HEr2Fe2 trigonal pyramids that share  a cornercorner with one Fe(1)Er6Fe6 cuboctahedra,  a cornercorner with one Fe(2)Er6Fe6 cuboctahedra, corners with eight equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(2)Er2Fe2 trigonal pyramids,  an edgeedge with one Fe(1)Er6Fe6 cuboctahedra,  an edgeedge with one H(2)Er2Fe2 trigonal pyramid, edges with two equivalent H(1)Er2Fe2 trigonal pyramids, and faces with two equivalent Fe(2)Er6Fe6 cuboctahedra. In the second H site, H(2) is bonded to one Er(1), one Er(2), and two equivalent Fe(3) atoms to form distorted HEr2Fe2 trigonal pyramids that share  a cornercorner with one Fe(1)Er6Fe6 cuboctahedra,  a cornercorner with one Fe(2)Er6Fe6 cuboctahedra, corners with four equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(1)Er2Fe2 trigonal pyramids, corners with four equivalent H(2)Er2Fe2 trigonal pyramids,  an edgeedge with one Fe(2)Er6Fe6 cuboctahedra, edges with two equivalent H(3)Er2Fe2 tetrahedra,  an edgeedge with one H(1)Er2Fe2 trigonal pyramid, and faces with two equivalent Fe(2)Er6Fe6 cuboctahedra. In the third H site, H(3) is bonded to two equivalent Er(2), one Fe(3), and one Fe(4) atom to form distorted HEr2Fe2 tetrahedra that share corners with two equivalent Fe(2)Er6Fe6 cuboctahedra, corners with four equivalent H(3)Er2Fe2 tetrahedra, corners with two equivalent H(2)Er2Fe2 trigonal pyramids, corners with four equivalent H(1)Er2Fe2 trigonal pyramids,  an edgeedge with one Fe(2)Er6Fe6 cuboctahedra, edges with two equivalent H(3)Er2Fe2 tetrahedra,  an edgeedge with one H(2)Er2Fe2 trigonal pyramid,  a faceface with one Fe(1)Er6Fe6 cuboctahedra, and  a faceface with one Fe(2)Er6Fe6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErFe2H3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.270
_cell_length_b   5.270
_cell_length_c   5.270
_cell_angle_alpha   63.945
_cell_angle_beta   63.945
_cell_angle_gamma   63.945
_symmetry_Int_Tables_number   1
_cell_volume   112.466
_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  0.133  0.133  0.133  1.0
  Er  Er1  1  0.867  0.867  0.867  1.0
  Fe  Fe2  1  0.500  0.500  0.500  1.0
  Fe  Fe3  1  0.500  1.000  0.500  1.0
  Fe  Fe4  1  0.500  0.500  0.000  1.0
  Fe  Fe5  1  0.000  0.500  0.500  1.0
  H  H6  1  0.138  0.546  0.138  1.0
  H  H7  1  0.138  0.138  0.546  1.0
  H  H8  1  0.546  0.138  0.138  1.0
  H  H9  1  0.862  0.454  0.862  1.0
  H  H10  1  0.862  0.862  0.454  1.0
  H  H11  1  0.454  0.862  0.862  1.0
[/CIF]
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