The material described by Yb3H8 crystallizes in the monoclinic C2/m space group. There are four inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 14-coordinate geometry to two equivalent H(1), two equivalent H(6), two equivalent H(8), four equivalent H(5), and four equivalent H(7) atoms. In the second Yb site, Yb(2) is bonded in a 14-coordinate geometry to two equivalent H(2), two equivalent H(6), two equivalent H(8), four equivalent H(5), and four equivalent H(7) atoms. In the third Yb site, Yb(3) is bonded in a 7-coordinate geometry to one H(1), one H(4), two equivalent H(2), and three equivalent H(3) atoms. In the fourth Yb site, Yb(4) is bonded in a body-centered cubic geometry to one H(1), one H(6), two equivalent H(2), two equivalent H(3), and two equivalent H(4) atoms. There are eight inequivalent H sites. In the first H site, H(6) is bonded to one Yb(1), one Yb(4), and two equivalent Yb(2) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the second H site, H(7) is bonded in a single-bond geometry to one Yb(1), two equivalent Yb(2), and one H(5) atom. In the third H site, H(8) is bonded in a 3-coordinate geometry to one Yb(1) and two equivalent Yb(2) atoms. In the fourth H site, H(1) is bonded to one Yb(1), one Yb(4), and two equivalent Yb(3) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the fifth H site, H(2) is bonded to one Yb(2), one Yb(4), and two equivalent Yb(3) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the sixth H site, H(3) is bonded to one Yb(4) and three equivalent Yb(3) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the seventh H site, H(4) is bonded to two equivalent Yb(3) and two equivalent Yb(4) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the eighth H site, H(5) is bonded in a distorted single-bond geometry to one Yb(1), two equivalent Yb(2), and one H(7) atom. is represented by the CIF file [CIF]
data_Yb3H8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.604
_cell_length_b   6.604
_cell_length_c   9.381
_cell_angle_alpha   89.917
_cell_angle_beta   89.917
_cell_angle_gamma   119.930
_symmetry_Int_Tables_number   1
_cell_volume   354.609
_cell_formula_units_Z   3
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
  Yb  Yb0  1  0.000  0.000  0.000  1.0
  Yb  Yb1  1  0.637  0.363  0.000  1.0
  Yb  Yb2  1  0.363  0.637  0.000  1.0
  Yb  Yb3  1  0.668  0.990  0.665  1.0
  Yb  Yb4  1  0.990  0.668  0.665  1.0
  Yb  Yb5  1  0.339  0.339  0.670  1.0
  Yb  Yb6  1  0.332  0.010  0.335  1.0
  Yb  Yb7  1  0.010  0.332  0.335  1.0
  Yb  Yb8  1  0.661  0.661  0.330  1.0
  H  H9  1  0.991  0.991  0.249  1.0
  H  H10  1  0.009  0.009  0.751  1.0
  H  H11  1  0.671  0.319  0.759  1.0
  H  H12  1  0.319  0.671  0.759  1.0
  H  H13  1  0.329  0.681  0.241  1.0
  H  H14  1  0.681  0.329  0.241  1.0
  H  H15  1  0.666  0.999  0.420  1.0
  H  H16  1  0.999  0.666  0.420  1.0
  H  H17  1  0.335  0.335  0.421  1.0
  H  H18  1  0.334  0.001  0.580  1.0
  H  H19  1  0.001  0.334  0.580  1.0
  H  H20  1  0.665  0.665  0.579  1.0
  H  H21  1  0.673  0.014  0.960  1.0
  H  H22  1  0.014  0.673  0.960  1.0
  H  H23  1  0.312  0.312  0.904  1.0
  H  H24  1  0.327  0.986  0.040  1.0
  H  H25  1  0.986  0.327  0.040  1.0
  H  H26  1  0.688  0.688  0.096  1.0
  H  H27  1  0.673  0.015  0.053  1.0
  H  H28  1  0.015  0.673  0.053  1.0
  H  H29  1  0.313  0.313  0.133  1.0
  H  H30  1  0.327  0.985  0.947  1.0
  H  H31  1  0.985  0.327  0.947  1.0
  H  H32  1  0.687  0.687  0.867  1.0
[/CIF]
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The material described by Yb3H8 crystallizes in the monoclinic C2/m space group. There are four inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 14-coordinate geometry to two equivalent H(1), two equivalent H(6), two equivalent H(8), four equivalent H(5), and four equivalent H(7) atoms. In the second Yb site, Yb(2) is bonded in a 14-coordinate geometry to two equivalent H(2), two equivalent H(6), two equivalent H(8), four equivalent H(5), and four equivalent H(7) atoms. In the third Yb site, Yb(3) is bonded in a 7-coordinate geometry to one H(1), one H(4), two equivalent H(2), and three equivalent H(3) atoms. In the fourth Yb site, Yb(4) is bonded in a body-centered cubic geometry to one H(1), one H(6), two equivalent H(2), two equivalent H(3), and two equivalent H(4) atoms. There are eight inequivalent H sites. In the first H site, H(6) is bonded to one Yb(1), one Yb(4), and two equivalent Yb(2) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the second H site, H(7) is bonded in a single-bond geometry to one Yb(1), two equivalent Yb(2), and one H(5) atom. In the third H site, H(8) is bonded in a 3-coordinate geometry to one Yb(1) and two equivalent Yb(2) atoms. In the fourth H site, H(1) is bonded to one Yb(1), one Yb(4), and two equivalent Yb(3) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the fifth H site, H(2) is bonded to one Yb(2), one Yb(4), and two equivalent Yb(3) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the sixth H site, H(3) is bonded to one Yb(4) and three equivalent Yb(3) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the seventh H site, H(4) is bonded to two equivalent Yb(3) and two equivalent Yb(4) atoms to form a mixture of corner and edge-sharing HYb4 tetrahedra. In the eighth H site, H(5) is bonded in a distorted single-bond geometry to one Yb(1), two equivalent Yb(2), and one H(7) atom. is represented by the CIF file [CIF]
data_Yb3H8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.604
_cell_length_b   6.604
_cell_length_c   9.381
_cell_angle_alpha   89.917
_cell_angle_beta   89.917
_cell_angle_gamma   119.930
_symmetry_Int_Tables_number   1
_cell_volume   354.609
_cell_formula_units_Z   3
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
  Yb  Yb0  1  0.000  0.000  0.000  1.0
  Yb  Yb1  1  0.637  0.363  0.000  1.0
  Yb  Yb2  1  0.363  0.637  0.000  1.0
  Yb  Yb3  1  0.668  0.990  0.665  1.0
  Yb  Yb4  1  0.990  0.668  0.665  1.0
  Yb  Yb5  1  0.339  0.339  0.670  1.0
  Yb  Yb6  1  0.332  0.010  0.335  1.0
  Yb  Yb7  1  0.010  0.332  0.335  1.0
  Yb  Yb8  1  0.661  0.661  0.330  1.0
  H  H9  1  0.991  0.991  0.249  1.0
  H  H10  1  0.009  0.009  0.751  1.0
  H  H11  1  0.671  0.319  0.759  1.0
  H  H12  1  0.319  0.671  0.759  1.0
  H  H13  1  0.329  0.681  0.241  1.0
  H  H14  1  0.681  0.329  0.241  1.0
  H  H15  1  0.666  0.999  0.420  1.0
  H  H16  1  0.999  0.666  0.420  1.0
  H  H17  1  0.335  0.335  0.421  1.0
  H  H18  1  0.334  0.001  0.580  1.0
  H  H19  1  0.001  0.334  0.580  1.0
  H  H20  1  0.665  0.665  0.579  1.0
  H  H21  1  0.673  0.014  0.960  1.0
  H  H22  1  0.014  0.673  0.960  1.0
  H  H23  1  0.312  0.312  0.904  1.0
  H  H24  1  0.327  0.986  0.040  1.0
  H  H25  1  0.986  0.327  0.040  1.0
  H  H26  1  0.688  0.688  0.096  1.0
  H  H27  1  0.673  0.015  0.053  1.0
  H  H28  1  0.015  0.673  0.053  1.0
  H  H29  1  0.313  0.313  0.133  1.0
  H  H30  1  0.327  0.985  0.947  1.0
  H  H31  1  0.985  0.327  0.947  1.0
  H  H32  1  0.687  0.687  0.867  1.0
[/CIF]
.