The material described by Ho4FeSe7 crystallizes in the monoclinic Cm space group. There are four inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 8-coordinate geometry to one Se(4), one Se(7), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(5) atoms. In the second Ho site, Ho(2) is bonded in a 7-coordinate geometry to one Se(3), two equivalent Se(1), two equivalent Se(4), and two equivalent Se(6) atoms. In the third Ho site, Ho(3) is bonded to one Se(5), one Se(6), two equivalent Se(3), and two equivalent Se(4) atoms to form HoSe6 octahedra that share  a cornercorner with one Ho(4)Se6 octahedra,  a cornercorner with one Fe(1)Se6 octahedra, and edges with two equivalent Ho(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 45-51°. In the fourth Ho site, Ho(4) is bonded to one Se(2), one Se(6), two equivalent Se(1), and two equivalent Se(7) atoms to form HoSe6 octahedra that share  a cornercorner with one Ho(3)Se6 octahedra, corners with two equivalent Fe(1)Se6 octahedra, edges with two equivalent Ho(4)Se6 octahedra, and edges with three equivalent Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 8-45°. Fe(1) is bonded to one Se(1), one Se(5), two equivalent Se(2), and two equivalent Se(7) atoms to form FeSe6 octahedra that share  a cornercorner with one Ho(3)Se6 octahedra, corners with two equivalent Ho(4)Se6 octahedra, edges with two equivalent Fe(1)Se6 octahedra, and edges with three equivalent Ho(4)Se6 octahedra. The corner-sharing octahedral tilt angles range from 8-51°. There are seven inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ho(2), two equivalent Ho(4), and one Fe(1) atom to form distorted SeHo4Fe trigonal bipyramids that share corners with four equivalent Se(6)Ho4 tetrahedra, corners with two equivalent Se(3)Ho5 trigonal bipyramids, corners with two equivalent Se(4)Ho5 trigonal bipyramids, edges with two equivalent Se(2)Ho3Fe2 square pyramids,  an edgeedge with one Se(6)Ho4 tetrahedra,  an edgeedge with one Se(4)Ho5 trigonal bipyramid, and edges with two equivalent Se(1)Ho4Fe trigonal bipyramids. In the second Se site, Se(2) is bonded to one Ho(4), two equivalent Ho(1), and two equivalent Fe(1) atoms to form SeHo3Fe2 square pyramids that share  a cornercorner with one Se(6)Ho4 tetrahedra, corners with two equivalent Se(3)Ho5 trigonal bipyramids, corners with two equivalent Se(4)Ho5 trigonal bipyramids, edges with two equivalent Se(2)Ho3Fe2 square pyramids,  an edgeedge with one Se(3)Ho5 trigonal bipyramid, and edges with two equivalent Se(1)Ho4Fe trigonal bipyramids. In the third Se site, Se(3) is bonded to one Ho(2), two equivalent Ho(1), and two equivalent Ho(3) atoms to form distorted SeHo5 trigonal bipyramids that share corners with two equivalent Se(2)Ho3Fe2 square pyramids, corners with two equivalent Se(1)Ho4Fe trigonal bipyramids, corners with two equivalent Se(4)Ho5 trigonal bipyramids,  an edgeedge with one Se(2)Ho3Fe2 square pyramid, edges with two equivalent Se(6)Ho4 tetrahedra, edges with two equivalent Se(3)Ho5 trigonal bipyramids, and edges with three equivalent Se(4)Ho5 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to one Ho(1), two equivalent Ho(2), and two equivalent Ho(3) atoms to form distorted SeHo5 trigonal bipyramids that share corners with two equivalent Se(2)Ho3Fe2 square pyramids, corners with four equivalent Se(6)Ho4 tetrahedra, corners with two equivalent Se(1)Ho4Fe trigonal bipyramids, corners with two equivalent Se(3)Ho5 trigonal bipyramids,  an edgeedge with one Se(6)Ho4 tetrahedra,  an edgeedge with one Se(1)Ho4Fe trigonal bipyramid, edges with two equivalent Se(4)Ho5 trigonal bipyramids, and edges with three equivalent Se(3)Ho5 trigonal bipyramids. In the fifth Se site, Se(5) is bonded in a distorted rectangular see-saw-like geometry to one Ho(3), two equivalent Ho(1), and one Fe(1) atom. In the sixth Se site, Se(6) is bonded to one Ho(3), one Ho(4), and two equivalent Ho(2) atoms to form SeHo4 tetrahedra that share  a cornercorner with one Se(2)Ho3Fe2 square pyramid, corners with two equivalent Se(6)Ho4 tetrahedra, corners with four equivalent Se(1)Ho4Fe trigonal bipyramids, corners with four equivalent Se(4)Ho5 trigonal bipyramids,  an edgeedge with one Se(1)Ho4Fe trigonal bipyramid,  an edgeedge with one Se(4)Ho5 trigonal bipyramid, and edges with two equivalent Se(3)Ho5 trigonal bipyramids. In the seventh Se site, Se(7) is bonded in a distorted rectangular see-saw-like geometry to one Ho(1), two equivalent Ho(4), and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho4FeSe7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.619
_cell_length_b   6.619
_cell_length_c   11.764
_cell_angle_alpha   76.492
_cell_angle_beta   76.492
_cell_angle_gamma   34.391
_symmetry_Int_Tables_number   1
_cell_volume   282.288
_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
  Ho  Ho0  1  0.696  0.696  0.213  1.0
  Ho  Ho1  1  0.306  0.306  0.797  1.0
  Ho  Ho2  1  0.999  0.999  0.011  1.0
  Ho  Ho3  1  0.107  0.107  0.557  1.0
  Fe  Fe4  1  0.888  0.888  0.428  1.0
  Se  Se5  1  0.751  0.751  0.625  1.0
  Se  Se6  1  0.282  0.282  0.360  1.0
  Se  Se7  1  0.334  0.334  0.054  1.0
  Se  Se8  1  0.661  0.661  0.947  1.0
  Se  Se9  1  0.027  0.027  0.238  1.0
  Se  Se10  1  0.968  0.968  0.783  1.0
  Se  Se11  1  0.480  0.480  0.486  1.0
[/CIF]
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The material described by Ho4FeSe7 crystallizes in the monoclinic Cm space group. There are four inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 8-coordinate geometry to one Se(4), one Se(7), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(5) atoms. In the second Ho site, Ho(2) is bonded in a 7-coordinate geometry to one Se(3), two equivalent Se(1), two equivalent Se(4), and two equivalent Se(6) atoms. In the third Ho site, Ho(3) is bonded to one Se(5), one Se(6), two equivalent Se(3), and two equivalent Se(4) atoms to form HoSe6 octahedra that share  a cornercorner with one Ho(4)Se6 octahedra,  a cornercorner with one Fe(1)Se6 octahedra, and edges with two equivalent Ho(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 45-51°. In the fourth Ho site, Ho(4) is bonded to one Se(2), one Se(6), two equivalent Se(1), and two equivalent Se(7) atoms to form HoSe6 octahedra that share  a cornercorner with one Ho(3)Se6 octahedra, corners with two equivalent Fe(1)Se6 octahedra, edges with two equivalent Ho(4)Se6 octahedra, and edges with three equivalent Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 8-45°. Fe(1) is bonded to one Se(1), one Se(5), two equivalent Se(2), and two equivalent Se(7) atoms to form FeSe6 octahedra that share  a cornercorner with one Ho(3)Se6 octahedra, corners with two equivalent Ho(4)Se6 octahedra, edges with two equivalent Fe(1)Se6 octahedra, and edges with three equivalent Ho(4)Se6 octahedra. The corner-sharing octahedral tilt angles range from 8-51°. There are seven inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ho(2), two equivalent Ho(4), and one Fe(1) atom to form distorted SeHo4Fe trigonal bipyramids that share corners with four equivalent Se(6)Ho4 tetrahedra, corners with two equivalent Se(3)Ho5 trigonal bipyramids, corners with two equivalent Se(4)Ho5 trigonal bipyramids, edges with two equivalent Se(2)Ho3Fe2 square pyramids,  an edgeedge with one Se(6)Ho4 tetrahedra,  an edgeedge with one Se(4)Ho5 trigonal bipyramid, and edges with two equivalent Se(1)Ho4Fe trigonal bipyramids. In the second Se site, Se(2) is bonded to one Ho(4), two equivalent Ho(1), and two equivalent Fe(1) atoms to form SeHo3Fe2 square pyramids that share  a cornercorner with one Se(6)Ho4 tetrahedra, corners with two equivalent Se(3)Ho5 trigonal bipyramids, corners with two equivalent Se(4)Ho5 trigonal bipyramids, edges with two equivalent Se(2)Ho3Fe2 square pyramids,  an edgeedge with one Se(3)Ho5 trigonal bipyramid, and edges with two equivalent Se(1)Ho4Fe trigonal bipyramids. In the third Se site, Se(3) is bonded to one Ho(2), two equivalent Ho(1), and two equivalent Ho(3) atoms to form distorted SeHo5 trigonal bipyramids that share corners with two equivalent Se(2)Ho3Fe2 square pyramids, corners with two equivalent Se(1)Ho4Fe trigonal bipyramids, corners with two equivalent Se(4)Ho5 trigonal bipyramids,  an edgeedge with one Se(2)Ho3Fe2 square pyramid, edges with two equivalent Se(6)Ho4 tetrahedra, edges with two equivalent Se(3)Ho5 trigonal bipyramids, and edges with three equivalent Se(4)Ho5 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to one Ho(1), two equivalent Ho(2), and two equivalent Ho(3) atoms to form distorted SeHo5 trigonal bipyramids that share corners with two equivalent Se(2)Ho3Fe2 square pyramids, corners with four equivalent Se(6)Ho4 tetrahedra, corners with two equivalent Se(1)Ho4Fe trigonal bipyramids, corners with two equivalent Se(3)Ho5 trigonal bipyramids,  an edgeedge with one Se(6)Ho4 tetrahedra,  an edgeedge with one Se(1)Ho4Fe trigonal bipyramid, edges with two equivalent Se(4)Ho5 trigonal bipyramids, and edges with three equivalent Se(3)Ho5 trigonal bipyramids. In the fifth Se site, Se(5) is bonded in a distorted rectangular see-saw-like geometry to one Ho(3), two equivalent Ho(1), and one Fe(1) atom. In the sixth Se site, Se(6) is bonded to one Ho(3), one Ho(4), and two equivalent Ho(2) atoms to form SeHo4 tetrahedra that share  a cornercorner with one Se(2)Ho3Fe2 square pyramid, corners with two equivalent Se(6)Ho4 tetrahedra, corners with four equivalent Se(1)Ho4Fe trigonal bipyramids, corners with four equivalent Se(4)Ho5 trigonal bipyramids,  an edgeedge with one Se(1)Ho4Fe trigonal bipyramid,  an edgeedge with one Se(4)Ho5 trigonal bipyramid, and edges with two equivalent Se(3)Ho5 trigonal bipyramids. In the seventh Se site, Se(7) is bonded in a distorted rectangular see-saw-like geometry to one Ho(1), two equivalent Ho(4), and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho4FeSe7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.619
_cell_length_b   6.619
_cell_length_c   11.764
_cell_angle_alpha   76.492
_cell_angle_beta   76.492
_cell_angle_gamma   34.391
_symmetry_Int_Tables_number   1
_cell_volume   282.288
_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
  Ho  Ho0  1  0.696  0.696  0.213  1.0
  Ho  Ho1  1  0.306  0.306  0.797  1.0
  Ho  Ho2  1  0.999  0.999  0.011  1.0
  Ho  Ho3  1  0.107  0.107  0.557  1.0
  Fe  Fe4  1  0.888  0.888  0.428  1.0
  Se  Se5  1  0.751  0.751  0.625  1.0
  Se  Se6  1  0.282  0.282  0.360  1.0
  Se  Se7  1  0.334  0.334  0.054  1.0
  Se  Se8  1  0.661  0.661  0.947  1.0
  Se  Se9  1  0.027  0.027  0.238  1.0
  Se  Se10  1  0.968  0.968  0.783  1.0
  Se  Se11  1  0.480  0.480  0.486  1.0
[/CIF]
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