The material structure described by Eu6Mg7H26 crystallizes in the monoclinic C2/m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one H(8), one H(9), two equivalent H(1), and two equivalent H(2) atoms to form distorted corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 30-50°. In the second Mg site, Mg(2) is bonded to one H(5), one H(6), two equivalent H(3), and two equivalent H(4) atoms to form corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 24-60°. In the third Mg site, Mg(3) is bonded to two equivalent H(4), two equivalent H(7), and two equivalent H(8) atoms to form a mixture of edge and corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 50-60°. In the fourth Mg site, Mg(4) is bonded to two equivalent H(9) and four equivalent H(3) atoms to form corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 24-30°. There are three inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 10-coordinate geometry to one H(7), one H(9), two equivalent H(4), two equivalent H(5), and four equivalent H(1) atoms. In the second Eu site, Eu(2) is bonded in a 11-coordinate geometry to two equivalent H(3), two equivalent H(4), three equivalent H(6), and four equivalent H(2) atoms. In the third Eu site, Eu(3) is bonded in a 7-coordinate geometry to one H(5), two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms. There are nine inequivalent H sites. In the first H site, H(3) is bonded in a 4-coordinate geometry to one Mg(2), one Mg(4), one Eu(2), and one Eu(3) atom. In the second H site, H(4) is bonded to one Mg(2), one Mg(3), one Eu(1), and one Eu(2) atom to form distorted HEu2Mg2 tetrahedra that share corners with two equivalent H(4)Eu2Mg2 tetrahedra, corners with four equivalent H(1)Eu3Mg tetrahedra, corners with four equivalent H(2)Eu3Mg tetrahedra, and  an edgeedge with one H(4)Eu2Mg2 tetrahedra. In the third H site, H(5) is bonded in a 2-coordinate geometry to one Mg(2), one Eu(3), and two equivalent Eu(1) atoms. In the fourth H site, H(6) is bonded in a distorted single-bond geometry to one Mg(2) and three equivalent Eu(2) atoms. In the fifth H site, H(7) is bonded in a distorted L-shaped geometry to two equivalent Mg(3) and one Eu(1) atom. In the sixth H site, H(8) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Mg(3) atoms. In the seventh H site, H(9) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(4), and one Eu(1) atom. In the eighth H site, H(1) is bonded to one Mg(1), one Eu(3), and two equivalent Eu(1) atoms to form distorted HEu3Mg tetrahedra that share corners with two equivalent H(1)Eu3Mg tetrahedra, corners with two equivalent H(2)Eu3Mg tetrahedra, corners with four equivalent H(4)Eu2Mg2 tetrahedra,  an edgeedge with one H(2)Eu3Mg tetrahedra, and edges with three equivalent H(1)Eu3Mg tetrahedra. In the ninth H site, H(2) is bonded to one Mg(1), one Eu(3), and two equivalent Eu(2) atoms to form distorted HEu3Mg tetrahedra that share corners with two equivalent H(1)Eu3Mg tetrahedra, corners with two equivalent H(2)Eu3Mg tetrahedra, corners with four equivalent H(4)Eu2Mg2 tetrahedra,  an edgeedge with one H(1)Eu3Mg tetrahedra, and edges with three equivalent H(2)Eu3Mg tetrahedra. is represented by the CIF card [CIF]
data_Eu6Mg7H26
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.314
_cell_length_b   9.314
_cell_length_c   11.355
_cell_angle_alpha   53.898
_cell_angle_beta   53.898
_cell_angle_gamma   34.566
_symmetry_Int_Tables_number   1
_cell_volume   439.811
_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
  Eu  Eu0  1  0.646  0.646  0.089  1.0
  Eu  Eu1  1  0.354  0.354  0.911  1.0
  Eu  Eu2  1  0.340  0.340  0.403  1.0
  Eu  Eu3  1  0.660  0.660  0.597  1.0
  Eu  Eu4  1  0.148  0.148  0.347  1.0
  Eu  Eu5  1  0.852  0.852  0.653  1.0
  Mg  Mg6  1  0.777  0.777  0.212  1.0
  Mg  Mg7  1  0.223  0.223  0.788  1.0
  Mg  Mg8  1  0.016  0.016  0.720  1.0
  Mg  Mg9  1  0.984  0.984  0.280  1.0
  Mg  Mg10  1  0.744  0.256  0.000  1.0
  Mg  Mg11  1  0.256  0.744  0.000  1.0
  Mg  Mg12  1  0.500  0.500  0.500  1.0
  H  H13  1  0.506  0.998  0.120  1.0
  H  H14  1  0.002  0.494  0.880  1.0
  H  H15  1  0.494  0.002  0.880  1.0
  H  H16  1  0.998  0.506  0.120  1.0
  H  H17  1  0.014  0.492  0.640  1.0
  H  H18  1  0.508  0.986  0.360  1.0
  H  H19  1  0.986  0.508  0.360  1.0
  H  H20  1  0.492  0.014  0.640  1.0
  H  H21  1  0.792  0.280  0.574  1.0
  H  H22  1  0.720  0.208  0.426  1.0
  H  H23  1  0.208  0.720  0.426  1.0
  H  H24  1  0.280  0.792  0.574  1.0
  H  H25  1  0.729  0.294  0.820  1.0
  H  H26  1  0.706  0.271  0.180  1.0
  H  H27  1  0.271  0.706  0.180  1.0
  H  H28  1  0.294  0.729  0.820  1.0
  H  H29  1  0.882  0.882  0.829  1.0
  H  H30  1  0.118  0.118  0.171  1.0
  H  H31  1  0.154  0.154  0.581  1.0
  H  H32  1  0.846  0.846  0.419  1.0
  H  H33  1  0.403  0.403  0.083  1.0
  H  H34  1  0.597  0.597  0.917  1.0
  H  H35  1  0.911  0.911  0.071  1.0
  H  H36  1  0.089  0.089  0.929  1.0
  H  H37  1  0.628  0.628  0.321  1.0
  H  H38  1  0.372  0.372  0.679  1.0
[/CIF]
.
The material structure described by Eu6Mg7H26 crystallizes in the monoclinic C2/m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one H(8), one H(9), two equivalent H(1), and two equivalent H(2) atoms to form distorted corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 30-50°. In the second Mg site, Mg(2) is bonded to one H(5), one H(6), two equivalent H(3), and two equivalent H(4) atoms to form corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 24-60°. In the third Mg site, Mg(3) is bonded to two equivalent H(4), two equivalent H(7), and two equivalent H(8) atoms to form a mixture of edge and corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 50-60°. In the fourth Mg site, Mg(4) is bonded to two equivalent H(9) and four equivalent H(3) atoms to form corner-sharing MgH6 octahedra. The corner-sharing octahedral tilt angles range from 24-30°. There are three inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 10-coordinate geometry to one H(7), one H(9), two equivalent H(4), two equivalent H(5), and four equivalent H(1) atoms. In the second Eu site, Eu(2) is bonded in a 11-coordinate geometry to two equivalent H(3), two equivalent H(4), three equivalent H(6), and four equivalent H(2) atoms. In the third Eu site, Eu(3) is bonded in a 7-coordinate geometry to one H(5), two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms. There are nine inequivalent H sites. In the first H site, H(3) is bonded in a 4-coordinate geometry to one Mg(2), one Mg(4), one Eu(2), and one Eu(3) atom. In the second H site, H(4) is bonded to one Mg(2), one Mg(3), one Eu(1), and one Eu(2) atom to form distorted HEu2Mg2 tetrahedra that share corners with two equivalent H(4)Eu2Mg2 tetrahedra, corners with four equivalent H(1)Eu3Mg tetrahedra, corners with four equivalent H(2)Eu3Mg tetrahedra, and  an edgeedge with one H(4)Eu2Mg2 tetrahedra. In the third H site, H(5) is bonded in a 2-coordinate geometry to one Mg(2), one Eu(3), and two equivalent Eu(1) atoms. In the fourth H site, H(6) is bonded in a distorted single-bond geometry to one Mg(2) and three equivalent Eu(2) atoms. In the fifth H site, H(7) is bonded in a distorted L-shaped geometry to two equivalent Mg(3) and one Eu(1) atom. In the sixth H site, H(8) is bonded in a distorted trigonal planar geometry to one Mg(1) and two equivalent Mg(3) atoms. In the seventh H site, H(9) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(4), and one Eu(1) atom. In the eighth H site, H(1) is bonded to one Mg(1), one Eu(3), and two equivalent Eu(1) atoms to form distorted HEu3Mg tetrahedra that share corners with two equivalent H(1)Eu3Mg tetrahedra, corners with two equivalent H(2)Eu3Mg tetrahedra, corners with four equivalent H(4)Eu2Mg2 tetrahedra,  an edgeedge with one H(2)Eu3Mg tetrahedra, and edges with three equivalent H(1)Eu3Mg tetrahedra. In the ninth H site, H(2) is bonded to one Mg(1), one Eu(3), and two equivalent Eu(2) atoms to form distorted HEu3Mg tetrahedra that share corners with two equivalent H(1)Eu3Mg tetrahedra, corners with two equivalent H(2)Eu3Mg tetrahedra, corners with four equivalent H(4)Eu2Mg2 tetrahedra,  an edgeedge with one H(1)Eu3Mg tetrahedra, and edges with three equivalent H(2)Eu3Mg tetrahedra. is represented by the CIF card [CIF]
data_Eu6Mg7H26
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.314
_cell_length_b   9.314
_cell_length_c   11.355
_cell_angle_alpha   53.898
_cell_angle_beta   53.898
_cell_angle_gamma   34.566
_symmetry_Int_Tables_number   1
_cell_volume   439.811
_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
  Eu  Eu0  1  0.646  0.646  0.089  1.0
  Eu  Eu1  1  0.354  0.354  0.911  1.0
  Eu  Eu2  1  0.340  0.340  0.403  1.0
  Eu  Eu3  1  0.660  0.660  0.597  1.0
  Eu  Eu4  1  0.148  0.148  0.347  1.0
  Eu  Eu5  1  0.852  0.852  0.653  1.0
  Mg  Mg6  1  0.777  0.777  0.212  1.0
  Mg  Mg7  1  0.223  0.223  0.788  1.0
  Mg  Mg8  1  0.016  0.016  0.720  1.0
  Mg  Mg9  1  0.984  0.984  0.280  1.0
  Mg  Mg10  1  0.744  0.256  0.000  1.0
  Mg  Mg11  1  0.256  0.744  0.000  1.0
  Mg  Mg12  1  0.500  0.500  0.500  1.0
  H  H13  1  0.506  0.998  0.120  1.0
  H  H14  1  0.002  0.494  0.880  1.0
  H  H15  1  0.494  0.002  0.880  1.0
  H  H16  1  0.998  0.506  0.120  1.0
  H  H17  1  0.014  0.492  0.640  1.0
  H  H18  1  0.508  0.986  0.360  1.0
  H  H19  1  0.986  0.508  0.360  1.0
  H  H20  1  0.492  0.014  0.640  1.0
  H  H21  1  0.792  0.280  0.574  1.0
  H  H22  1  0.720  0.208  0.426  1.0
  H  H23  1  0.208  0.720  0.426  1.0
  H  H24  1  0.280  0.792  0.574  1.0
  H  H25  1  0.729  0.294  0.820  1.0
  H  H26  1  0.706  0.271  0.180  1.0
  H  H27  1  0.271  0.706  0.180  1.0
  H  H28  1  0.294  0.729  0.820  1.0
  H  H29  1  0.882  0.882  0.829  1.0
  H  H30  1  0.118  0.118  0.171  1.0
  H  H31  1  0.154  0.154  0.581  1.0
  H  H32  1  0.846  0.846  0.419  1.0
  H  H33  1  0.403  0.403  0.083  1.0
  H  H34  1  0.597  0.597  0.917  1.0
  H  H35  1  0.911  0.911  0.071  1.0
  H  H36  1  0.089  0.089  0.929  1.0
  H  H37  1  0.628  0.628  0.321  1.0
  H  H38  1  0.372  0.372  0.679  1.0
[/CIF]
.