The structure described by Rb3MgH5 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 4-coordinate geometry to two equivalent H(1) and two equivalent H(2) atoms. In the second Rb site, Rb(2) is bonded in a linear geometry to two equivalent H(2) atoms. Mg(1) is bonded in a tetrahedral geometry to four equivalent H(1) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded in a 1-coordinate geometry to one Rb(1) and one Mg(1) atom. In the second H site, H(2) is bonded to two equivalent Rb(2) and four equivalent Rb(1) atoms to form corner-sharing HRb6 octahedra. The corner-sharing octahedral tilt angles range from 0-29°. is represented by the CIF file [CIF]
data_Rb3MgH5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.377
_cell_length_b   8.377
_cell_length_c   8.377
_cell_angle_alpha   122.760
_cell_angle_beta   122.760
_cell_angle_gamma   85.282
_symmetry_Int_Tables_number   1
_cell_volume   396.805
_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
  Rb  Rb0  1  0.186  0.686  0.871  1.0
  Rb  Rb1  1  0.814  0.314  0.129  1.0
  Rb  Rb2  1  0.686  0.814  0.500  1.0
  Rb  Rb3  1  0.314  0.186  0.500  1.0
  Rb  Rb4  1  0.250  0.250  0.000  1.0
  Rb  Rb5  1  0.750  0.750  0.000  1.0
  Mg  Mg6  1  0.250  0.750  0.500  1.0
  Mg  Mg7  1  0.750  0.250  0.500  1.0
  H  H8  1  0.471  0.971  0.758  1.0
  H  H9  1  0.213  0.713  0.242  1.0
  H  H10  1  0.971  0.213  0.500  1.0
  H  H11  1  0.713  0.471  0.500  1.0
  H  H12  1  0.529  0.029  0.242  1.0
  H  H13  1  0.787  0.287  0.758  1.0
  H  H14  1  0.029  0.787  0.500  1.0
  H  H15  1  0.287  0.529  0.500  1.0
  H  H16  1  0.500  0.500  0.000  1.0
  H  H17  1  0.000  0.000  0.000  1.0
[/CIF]
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The structure described by Rb3MgH5 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 4-coordinate geometry to two equivalent H(1) and two equivalent H(2) atoms. In the second Rb site, Rb(2) is bonded in a linear geometry to two equivalent H(2) atoms. Mg(1) is bonded in a tetrahedral geometry to four equivalent H(1) atoms. There are two inequivalent H sites. In the first H site, H(1) is bonded in a 1-coordinate geometry to one Rb(1) and one Mg(1) atom. In the second H site, H(2) is bonded to two equivalent Rb(2) and four equivalent Rb(1) atoms to form corner-sharing HRb6 octahedra. The corner-sharing octahedral tilt angles range from 0-29°. is represented by the CIF file [CIF]
data_Rb3MgH5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.377
_cell_length_b   8.377
_cell_length_c   8.377
_cell_angle_alpha   122.760
_cell_angle_beta   122.760
_cell_angle_gamma   85.282
_symmetry_Int_Tables_number   1
_cell_volume   396.805
_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
  Rb  Rb0  1  0.186  0.686  0.871  1.0
  Rb  Rb1  1  0.814  0.314  0.129  1.0
  Rb  Rb2  1  0.686  0.814  0.500  1.0
  Rb  Rb3  1  0.314  0.186  0.500  1.0
  Rb  Rb4  1  0.250  0.250  0.000  1.0
  Rb  Rb5  1  0.750  0.750  0.000  1.0
  Mg  Mg6  1  0.250  0.750  0.500  1.0
  Mg  Mg7  1  0.750  0.250  0.500  1.0
  H  H8  1  0.471  0.971  0.758  1.0
  H  H9  1  0.213  0.713  0.242  1.0
  H  H10  1  0.971  0.213  0.500  1.0
  H  H11  1  0.713  0.471  0.500  1.0
  H  H12  1  0.529  0.029  0.242  1.0
  H  H13  1  0.787  0.287  0.758  1.0
  H  H14  1  0.029  0.787  0.500  1.0
  H  H15  1  0.287  0.529  0.500  1.0
  H  H16  1  0.500  0.500  0.000  1.0
  H  H17  1  0.000  0.000  0.000  1.0
[/CIF]
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