The crystal structure described by Rb2MgH4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a distorted single-bond geometry to one H(2) atom. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to one H(2), two equivalent H(3), and four equivalent H(1) atoms. Mg(1) is bonded in a tetrahedral geometry to one H(2), one H(3), and two equivalent H(1) atoms. There are three inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to two equivalent Rb(2) and one Mg(1) atom. In the second H site, H(2) is bonded in a 3-coordinate geometry to one Rb(1), one Rb(2), and one Mg(1) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to two equivalent Rb(2) and one Mg(1) atom. is represented by the CIF card [CIF]
data_Rb2MgH4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.398
_cell_length_b   8.267
_cell_length_c   11.237
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   594.341
_cell_formula_units_Z   4
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
  Rb  Rb0  1  0.250  0.663  0.085  1.0
  Rb  Rb1  1  0.250  0.163  0.415  1.0
  Rb  Rb2  1  0.750  0.337  0.915  1.0
  Rb  Rb3  1  0.750  0.837  0.585  1.0
  Rb  Rb4  1  0.250  0.993  0.800  1.0
  Rb  Rb5  1  0.250  0.493  0.700  1.0
  Rb  Rb6  1  0.750  0.007  0.200  1.0
  Rb  Rb7  1  0.750  0.507  0.300  1.0
  Mg  Mg8  1  0.250  0.727  0.420  1.0
  Mg  Mg9  1  0.250  0.227  0.080  1.0
  Mg  Mg10  1  0.750  0.273  0.580  1.0
  Mg  Mg11  1  0.750  0.773  0.920  1.0
  H  H12  1  0.013  0.805  0.345  1.0
  H  H13  1  0.487  0.305  0.155  1.0
  H  H14  1  0.513  0.195  0.655  1.0
  H  H15  1  0.987  0.695  0.845  1.0
  H  H16  1  0.987  0.195  0.655  1.0
  H  H17  1  0.513  0.695  0.845  1.0
  H  H18  1  0.487  0.805  0.345  1.0
  H  H19  1  0.013  0.305  0.155  1.0
  H  H20  1  0.250  0.505  0.421  1.0
  H  H21  1  0.250  0.005  0.079  1.0
  H  H22  1  0.750  0.495  0.579  1.0
  H  H23  1  0.750  0.995  0.921  1.0
  H  H24  1  0.250  0.315  0.928  1.0
  H  H25  1  0.250  0.815  0.572  1.0
  H  H26  1  0.750  0.685  0.072  1.0
  H  H27  1  0.750  0.185  0.428  1.0
[/CIF]
.
The crystal structure described by Rb2MgH4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a distorted single-bond geometry to one H(2) atom. In the second Rb site, Rb(2) is bonded in a 7-coordinate geometry to one H(2), two equivalent H(3), and four equivalent H(1) atoms. Mg(1) is bonded in a tetrahedral geometry to one H(2), one H(3), and two equivalent H(1) atoms. There are three inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to two equivalent Rb(2) and one Mg(1) atom. In the second H site, H(2) is bonded in a 3-coordinate geometry to one Rb(1), one Rb(2), and one Mg(1) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to two equivalent Rb(2) and one Mg(1) atom. is represented by the CIF card [CIF]
data_Rb2MgH4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.398
_cell_length_b   8.267
_cell_length_c   11.237
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   594.341
_cell_formula_units_Z   4
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
  Rb  Rb0  1  0.250  0.663  0.085  1.0
  Rb  Rb1  1  0.250  0.163  0.415  1.0
  Rb  Rb2  1  0.750  0.337  0.915  1.0
  Rb  Rb3  1  0.750  0.837  0.585  1.0
  Rb  Rb4  1  0.250  0.993  0.800  1.0
  Rb  Rb5  1  0.250  0.493  0.700  1.0
  Rb  Rb6  1  0.750  0.007  0.200  1.0
  Rb  Rb7  1  0.750  0.507  0.300  1.0
  Mg  Mg8  1  0.250  0.727  0.420  1.0
  Mg  Mg9  1  0.250  0.227  0.080  1.0
  Mg  Mg10  1  0.750  0.273  0.580  1.0
  Mg  Mg11  1  0.750  0.773  0.920  1.0
  H  H12  1  0.013  0.805  0.345  1.0
  H  H13  1  0.487  0.305  0.155  1.0
  H  H14  1  0.513  0.195  0.655  1.0
  H  H15  1  0.987  0.695  0.845  1.0
  H  H16  1  0.987  0.195  0.655  1.0
  H  H17  1  0.513  0.695  0.845  1.0
  H  H18  1  0.487  0.805  0.345  1.0
  H  H19  1  0.013  0.305  0.155  1.0
  H  H20  1  0.250  0.505  0.421  1.0
  H  H21  1  0.250  0.005  0.079  1.0
  H  H22  1  0.750  0.495  0.579  1.0
  H  H23  1  0.750  0.995  0.921  1.0
  H  H24  1  0.250  0.315  0.928  1.0
  H  H25  1  0.250  0.815  0.572  1.0
  H  H26  1  0.750  0.685  0.072  1.0
  H  H27  1  0.750  0.185  0.428  1.0
[/CIF]
.