The crystal structure described by MgFe2CuAs2(HO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(5), one O(7), and one O(8) atom to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Fe(2)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one As(1)O4 tetrahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-49°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(5), one O(8), and one O(9) atom to form distorted FeO5 square pyramids that share corners with two equivalent As(1)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid,  an edgeedge with one Fe(2)O6 octahedra, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. In the second Fe site, Fe(2) is bonded to one O(10), one O(2), one O(4), one O(6), one O(7), and one O(9) atom to form distorted FeO6 octahedra that share  a cornercorner with one As(1)O4 tetrahedra, corners with two equivalent Mg(1)O5 trigonal bipyramids, and  an edgeedge with one Fe(1)O5 square pyramid. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(2), one O(5), one O(6), and one O(9) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form AsO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 55°. In the second As site, As(2) is bonded in a trigonal non-coplanar geometry to one O(2), one O(6), and one O(8) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(3) and one O(8) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(2), one Cu(1), and one As(2) atom. In the third O site, O(3) is bonded in a water-like geometry to one As(1) and one H(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Mg(1), one Fe(2), and one H(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), one Cu(1), and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(2), one Cu(1), and one As(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(2), and one As(1) atom. In the eighth O site, O(8) is bonded in a distorted tetrahedral geometry to one Mg(1), one Fe(1), one As(2), and one H(1) atom. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to one Fe(1), one Fe(2), and one Cu(1) atom. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Fe(1), one Fe(2), and one Cu(1) atom. is represented by the CIF card [CIF]
data_MgFe2CuAs2(HO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.532
_cell_length_b   5.786
_cell_length_c   7.819
_cell_angle_alpha   110.459
_cell_angle_beta   98.363
_cell_angle_gamma   105.775
_symmetry_Int_Tables_number   1
_cell_volume   217.473
_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
  Mg  Mg0  1  0.822  0.845  0.570  1.0
  Fe  Fe1  1  0.840  0.388  0.838  1.0
  Fe  Fe2  1  0.199  0.619  0.210  1.0
  Cu  Cu3  1  0.023  0.010  0.036  1.0
  As  As4  1  0.301  0.762  0.681  1.0
  As  As5  1  0.696  0.233  0.353  1.0
  H  H6  1  0.166  0.324  0.595  1.0
  H  H7  1  0.649  0.633  0.227  1.0
  O  O8  1  0.612  0.976  0.776  1.0
  O  O9  1  0.431  0.956  0.202  1.0
  O  O10  1  0.352  0.462  0.640  1.0
  O  O11  1  0.553  0.617  0.323  1.0
  O  O12  1  0.043  0.768  0.786  1.0
  O  O13  1  0.947  0.254  0.232  1.0
  O  O14  1  0.152  0.791  0.482  1.0
  O  O15  1  0.861  0.190  0.562  1.0
  O  O16  1  0.134  0.305  0.974  1.0
  O  O17  1  0.904  0.691  0.082  1.0
[/CIF]
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The crystal structure described by MgFe2CuAs2(HO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(5), one O(7), and one O(8) atom to form distorted MgO5 trigonal bipyramids that share corners with two equivalent Fe(2)O6 octahedra,  a cornercorner with one Fe(1)O5 square pyramid,  a cornercorner with one As(1)O4 tetrahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one As(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-49°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(5), one O(8), and one O(9) atom to form distorted FeO5 square pyramids that share corners with two equivalent As(1)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid,  an edgeedge with one Fe(2)O6 octahedra, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. In the second Fe site, Fe(2) is bonded to one O(10), one O(2), one O(4), one O(6), one O(7), and one O(9) atom to form distorted FeO6 octahedra that share  a cornercorner with one As(1)O4 tetrahedra, corners with two equivalent Mg(1)O5 trigonal bipyramids, and  an edgeedge with one Fe(1)O5 square pyramid. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(2), one O(5), one O(6), and one O(9) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form AsO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 55°. In the second As site, As(2) is bonded in a trigonal non-coplanar geometry to one O(2), one O(6), and one O(8) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a distorted linear geometry to one O(3) and one O(8) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(4) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one As(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(2), one Cu(1), and one As(2) atom. In the third O site, O(3) is bonded in a water-like geometry to one As(1) and one H(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Mg(1), one Fe(2), and one H(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), one Cu(1), and one As(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(2), one Cu(1), and one As(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(2), and one As(1) atom. In the eighth O site, O(8) is bonded in a distorted tetrahedral geometry to one Mg(1), one Fe(1), one As(2), and one H(1) atom. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to one Fe(1), one Fe(2), and one Cu(1) atom. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Fe(1), one Fe(2), and one Cu(1) atom. is represented by the CIF card [CIF]
data_MgFe2CuAs2(HO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.532
_cell_length_b   5.786
_cell_length_c   7.819
_cell_angle_alpha   110.459
_cell_angle_beta   98.363
_cell_angle_gamma   105.775
_symmetry_Int_Tables_number   1
_cell_volume   217.473
_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
  Mg  Mg0  1  0.822  0.845  0.570  1.0
  Fe  Fe1  1  0.840  0.388  0.838  1.0
  Fe  Fe2  1  0.199  0.619  0.210  1.0
  Cu  Cu3  1  0.023  0.010  0.036  1.0
  As  As4  1  0.301  0.762  0.681  1.0
  As  As5  1  0.696  0.233  0.353  1.0
  H  H6  1  0.166  0.324  0.595  1.0
  H  H7  1  0.649  0.633  0.227  1.0
  O  O8  1  0.612  0.976  0.776  1.0
  O  O9  1  0.431  0.956  0.202  1.0
  O  O10  1  0.352  0.462  0.640  1.0
  O  O11  1  0.553  0.617  0.323  1.0
  O  O12  1  0.043  0.768  0.786  1.0
  O  O13  1  0.947  0.254  0.232  1.0
  O  O14  1  0.152  0.791  0.482  1.0
  O  O15  1  0.861  0.190  0.562  1.0
  O  O16  1  0.134  0.305  0.974  1.0
  O  O17  1  0.904  0.691  0.082  1.0
[/CIF]
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