The material structure described by Li2MgH4 crystallizes in the orthorhombic Pbam space group. Li(1) is bonded to two equivalent H(1) and four equivalent H(2) atoms to form distorted LiH6 octahedra that share corners with four equivalent Li(1)H6 octahedra, corners with four equivalent Mg(1)H6 octahedra, edges with two equivalent Li(1)H6 octahedra, edges with two equivalent Mg(1)H6 octahedra, and faces with two equivalent Li(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 38-61°. Mg(1) is bonded to two equivalent H(2) and four equivalent H(1) atoms to form MgH6 octahedra that share corners with eight equivalent Li(1)H6 octahedra, edges with two equivalent Mg(1)H6 octahedra, and edges with four equivalent Li(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 48-61°. There are two inequivalent H sites. In the first H site, H(2) is bonded to four equivalent Li(1) and one Mg(1) atom to form distorted HLi4Mg trigonal bipyramids that share corners with five equivalent H(2)Li4Mg trigonal bipyramids, corners with four equivalent H(1)Li2Mg2 trigonal pyramids, edges with four equivalent H(2)Li4Mg trigonal bipyramids, and edges with four equivalent H(1)Li2Mg2 trigonal pyramids. In the second H site, H(1) is bonded to two equivalent Li(1) and two equivalent Mg(1) atoms to form HLi2Mg2 trigonal pyramids that share corners with four equivalent H(2)Li4Mg trigonal bipyramids, corners with six equivalent H(1)Li2Mg2 trigonal pyramids, edges with four equivalent H(2)Li4Mg trigonal bipyramids, and  an edgeedge with one H(1)Li2Mg2 trigonal pyramid. is represented by the CIF card [CIF]
data_Li2MgH4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.925
_cell_length_b   4.924
_cell_length_c   9.301
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   133.939
_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
  Li  Li0  1  0.500  0.982  0.289  1.0
  Li  Li1  1  0.500  0.018  0.711  1.0
  Li  Li2  1  0.500  0.482  0.211  1.0
  Li  Li3  1  0.500  0.518  0.789  1.0
  Mg  Mg4  1  0.000  0.500  0.500  1.0
  Mg  Mg5  1  0.000  0.000  0.000  1.0
  H  H6  1  0.500  0.706  0.587  1.0
  H  H7  1  0.500  0.294  0.413  1.0
  H  H8  1  0.500  0.206  0.913  1.0
  H  H9  1  0.500  0.794  0.087  1.0
  H  H10  1  0.000  0.718  0.323  1.0
  H  H11  1  0.000  0.282  0.677  1.0
  H  H12  1  0.000  0.218  0.177  1.0
  H  H13  1  0.000  0.782  0.823  1.0
[/CIF]
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The material structure described by Li2MgH4 crystallizes in the orthorhombic Pbam space group. Li(1) is bonded to two equivalent H(1) and four equivalent H(2) atoms to form distorted LiH6 octahedra that share corners with four equivalent Li(1)H6 octahedra, corners with four equivalent Mg(1)H6 octahedra, edges with two equivalent Li(1)H6 octahedra, edges with two equivalent Mg(1)H6 octahedra, and faces with two equivalent Li(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 38-61°. Mg(1) is bonded to two equivalent H(2) and four equivalent H(1) atoms to form MgH6 octahedra that share corners with eight equivalent Li(1)H6 octahedra, edges with two equivalent Mg(1)H6 octahedra, and edges with four equivalent Li(1)H6 octahedra. The corner-sharing octahedral tilt angles range from 48-61°. There are two inequivalent H sites. In the first H site, H(2) is bonded to four equivalent Li(1) and one Mg(1) atom to form distorted HLi4Mg trigonal bipyramids that share corners with five equivalent H(2)Li4Mg trigonal bipyramids, corners with four equivalent H(1)Li2Mg2 trigonal pyramids, edges with four equivalent H(2)Li4Mg trigonal bipyramids, and edges with four equivalent H(1)Li2Mg2 trigonal pyramids. In the second H site, H(1) is bonded to two equivalent Li(1) and two equivalent Mg(1) atoms to form HLi2Mg2 trigonal pyramids that share corners with four equivalent H(2)Li4Mg trigonal bipyramids, corners with six equivalent H(1)Li2Mg2 trigonal pyramids, edges with four equivalent H(2)Li4Mg trigonal bipyramids, and  an edgeedge with one H(1)Li2Mg2 trigonal pyramid. is represented by the CIF card [CIF]
data_Li2MgH4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.925
_cell_length_b   4.924
_cell_length_c   9.301
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   133.939
_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
  Li  Li0  1  0.500  0.982  0.289  1.0
  Li  Li1  1  0.500  0.018  0.711  1.0
  Li  Li2  1  0.500  0.482  0.211  1.0
  Li  Li3  1  0.500  0.518  0.789  1.0
  Mg  Mg4  1  0.000  0.500  0.500  1.0
  Mg  Mg5  1  0.000  0.000  0.000  1.0
  H  H6  1  0.500  0.706  0.587  1.0
  H  H7  1  0.500  0.294  0.413  1.0
  H  H8  1  0.500  0.206  0.913  1.0
  H  H9  1  0.500  0.794  0.087  1.0
  H  H10  1  0.000  0.718  0.323  1.0
  H  H11  1  0.000  0.282  0.677  1.0
  H  H12  1  0.000  0.218  0.177  1.0
  H  H13  1  0.000  0.782  0.823  1.0
[/CIF]
.