The material described by Y10H21 is alpha bismuth trifluoride-like structured and crystallizes in the triclinic P-1 space group. There are five inequivalent Y sites. In the first Y site, Y(1) is bonded in a distorted body-centered cubic geometry to one H(10), one H(11), one H(4), one H(5), one H(6), one H(8), one H(9), and two equivalent H(2) atoms. In the second Y site, Y(2) is bonded in a body-centered cubic geometry to one H(10), one H(3), one H(7), one H(8), two equivalent H(1), and two equivalent H(4) atoms. In the third Y site, Y(3) is bonded in a distorted body-centered cubic geometry to one H(1), one H(10), one H(11), one H(2), one H(5), one H(8), one H(9), and two equivalent H(6) atoms. In the fourth Y site, Y(4) is bonded in a body-centered cubic geometry to one H(2), one H(3), one H(4), one H(5), one H(8), one H(9), and two equivalent H(7) atoms. In the fifth Y site, Y(5) is bonded in a distorted body-centered cubic geometry to one H(1), one H(10), one H(11), one H(5), one H(6), one H(7), one H(9), and two equivalent H(3) atoms. There are eleven inequivalent H sites. In the first H site, H(1) is bonded to one Y(3), one Y(5), and two equivalent Y(2) atoms to form HY4 tetrahedra that share corners with two equivalent H(11)Y6 octahedra,  a cornercorner with one H(2)Y4 tetrahedra,  a cornercorner with one H(6)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra, corners with two equivalent H(10)Y4 tetrahedra, corners with two equivalent H(3)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with four equivalent H(4)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra, and  an edgeedge with one H(8)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the second H site, H(2) is bonded to one Y(3), one Y(4), and two equivalent Y(1) atoms to form HY4 tetrahedra that share corners with three equivalent H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(7)Y4 tetrahedra, corners with two equivalent H(8)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with three equivalent H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra, and  an edgeedge with one H(9)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the third H site, H(3) is bonded to one Y(2), one Y(4), and two equivalent Y(5) atoms to form HY4 tetrahedra that share corners with two equivalent H(11)Y6 octahedra,  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(2)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra,  a cornercorner with one H(5)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(8)Y4 tetrahedra, corners with three equivalent H(7)Y4 tetrahedra, corners with three equivalent H(9)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra, and  an edgeedge with one H(7)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the fourth H site, H(4) is bonded to one Y(1), one Y(4), and two equivalent Y(2) atoms to form HY4 tetrahedra that share  a cornercorner with one H(11)Y6 octahedra,  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(2)Y4 tetrahedra,  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(6)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(7)Y4 tetrahedra, corners with two equivalent H(8)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with four equivalent H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra, and  an edgeedge with one H(8)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the fifth H site, H(5) is bonded to one Y(1), one Y(3), one Y(4), and one Y(5) atom to form HY4 tetrahedra that share  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with three equivalent H(7)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra,  an edgeedge with one H(9)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. In the sixth H site, H(6) is bonded to one Y(1), one Y(5), and two equivalent Y(3) atoms to form HY4 tetrahedra that share  a cornercorner with one H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra, corners with two equivalent H(10)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(3)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with three equivalent H(8)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(9)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. The corner-sharing octahedral tilt angles are 55°. In the seventh H site, H(7) is bonded to one Y(2), one Y(5), and two equivalent Y(4) atoms to form HY4 tetrahedra that share  a cornercorner with one H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(6)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra,  a cornercorner with one H(9)Y4 tetrahedra, corners with two equivalent H(10)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with three equivalent H(3)Y4 tetrahedra, corners with three equivalent H(5)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra, and  an edgeedge with one H(9)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the eighth H site, H(8) is bonded to one Y(1), one Y(2), one Y(3), and one Y(4) atom to form HY4 tetrahedra that share corners with two equivalent H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(5)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra,  a cornercorner with one H(9)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(3)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with three equivalent H(10)Y4 tetrahedra, corners with three equivalent H(6)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra, and  an edgeedge with one H(9)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the ninth H site, H(9) is bonded to one Y(1), one Y(3), one Y(4), and one Y(5) atom to form HY4 tetrahedra that share  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with three equivalent H(3)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. In the tenth H site, H(10) is bonded to one Y(1), one Y(2), one Y(3), and one Y(5) atom to form HY4 tetrahedra that share  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra,  a cornercorner with one H(5)Y4 tetrahedra,  a cornercorner with one H(9)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(7)Y4 tetrahedra, corners with three equivalent H(2)Y4 tetrahedra, corners with three equivalent H(8)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(9)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. In the eleventh H site, H(11) is bonded to two equivalent Y(1), two equivalent Y(3), and two equivalent Y(5) atoms to form a mixture of corner and face-sharing HY6 octahedra. is represented by the CIF file [CIF]
data_Y10H21
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.367
_cell_length_b   7.349
_cell_length_c   8.205
_cell_angle_alpha   102.946
_cell_angle_beta   97.333
_cell_angle_gamma   106.859
_symmetry_Int_Tables_number   1
_cell_volume   350.350
_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
  Y  Y0  1  0.703  0.653  0.901  1.0
  Y  Y1  1  0.500  0.250  0.501  1.0
  Y  Y2  1  0.297  0.851  0.100  1.0
  Y  Y3  1  0.703  0.149  0.900  1.0
  Y  Y4  1  0.101  0.449  0.700  1.0
  Y  Y5  1  0.500  0.750  0.499  1.0
  Y  Y6  1  0.901  0.049  0.297  1.0
  Y  Y7  1  0.297  0.347  0.099  1.0
  Y  Y8  1  0.099  0.951  0.703  1.0
  Y  Y9  1  0.899  0.551  0.300  1.0
  H  H10  1  0.550  0.975  0.349  1.0
  H  H11  1  0.351  0.575  0.951  1.0
  H  H12  1  0.149  0.173  0.549  1.0
  H  H13  1  0.649  0.425  0.049  1.0
  H  H14  1  0.549  0.474  0.349  1.0
  H  H15  1  0.450  0.025  0.651  1.0
  H  H16  1  0.948  0.769  0.154  1.0
  H  H17  1  0.361  0.077  0.949  1.0
  H  H18  1  0.639  0.923  0.051  1.0
  H  H19  1  0.150  0.677  0.550  1.0
  H  H20  1  0.249  0.624  0.249  1.0
  H  H21  1  0.751  0.376  0.751  1.0
  H  H22  1  0.948  0.282  0.154  1.0
  H  H23  1  0.052  0.231  0.846  1.0
  H  H24  1  0.451  0.526  0.651  1.0
  H  H25  1  0.851  0.827  0.451  1.0
  H  H26  1  0.257  0.128  0.256  1.0
  H  H27  1  0.743  0.872  0.744  1.0
  H  H28  1  0.000  0.000  0.000  1.0
  H  H29  1  0.052  0.718  0.846  1.0
  H  H30  1  0.850  0.323  0.450  1.0
[/CIF]
.
The material described by Y10H21 is alpha bismuth trifluoride-like structured and crystallizes in the triclinic P-1 space group. There are five inequivalent Y sites. In the first Y site, Y(1) is bonded in a distorted body-centered cubic geometry to one H(10), one H(11), one H(4), one H(5), one H(6), one H(8), one H(9), and two equivalent H(2) atoms. In the second Y site, Y(2) is bonded in a body-centered cubic geometry to one H(10), one H(3), one H(7), one H(8), two equivalent H(1), and two equivalent H(4) atoms. In the third Y site, Y(3) is bonded in a distorted body-centered cubic geometry to one H(1), one H(10), one H(11), one H(2), one H(5), one H(8), one H(9), and two equivalent H(6) atoms. In the fourth Y site, Y(4) is bonded in a body-centered cubic geometry to one H(2), one H(3), one H(4), one H(5), one H(8), one H(9), and two equivalent H(7) atoms. In the fifth Y site, Y(5) is bonded in a distorted body-centered cubic geometry to one H(1), one H(10), one H(11), one H(5), one H(6), one H(7), one H(9), and two equivalent H(3) atoms. There are eleven inequivalent H sites. In the first H site, H(1) is bonded to one Y(3), one Y(5), and two equivalent Y(2) atoms to form HY4 tetrahedra that share corners with two equivalent H(11)Y6 octahedra,  a cornercorner with one H(2)Y4 tetrahedra,  a cornercorner with one H(6)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra, corners with two equivalent H(10)Y4 tetrahedra, corners with two equivalent H(3)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with four equivalent H(4)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra, and  an edgeedge with one H(8)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the second H site, H(2) is bonded to one Y(3), one Y(4), and two equivalent Y(1) atoms to form HY4 tetrahedra that share corners with three equivalent H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(7)Y4 tetrahedra, corners with two equivalent H(8)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with three equivalent H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra, and  an edgeedge with one H(9)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the third H site, H(3) is bonded to one Y(2), one Y(4), and two equivalent Y(5) atoms to form HY4 tetrahedra that share corners with two equivalent H(11)Y6 octahedra,  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(2)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra,  a cornercorner with one H(5)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(8)Y4 tetrahedra, corners with three equivalent H(7)Y4 tetrahedra, corners with three equivalent H(9)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra, and  an edgeedge with one H(7)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the fourth H site, H(4) is bonded to one Y(1), one Y(4), and two equivalent Y(2) atoms to form HY4 tetrahedra that share  a cornercorner with one H(11)Y6 octahedra,  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(2)Y4 tetrahedra,  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(6)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(7)Y4 tetrahedra, corners with two equivalent H(8)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with four equivalent H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra, and  an edgeedge with one H(8)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the fifth H site, H(5) is bonded to one Y(1), one Y(3), one Y(4), and one Y(5) atom to form HY4 tetrahedra that share  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with three equivalent H(7)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra,  an edgeedge with one H(9)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. In the sixth H site, H(6) is bonded to one Y(1), one Y(5), and two equivalent Y(3) atoms to form HY4 tetrahedra that share  a cornercorner with one H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra, corners with two equivalent H(10)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(3)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(9)Y4 tetrahedra, corners with three equivalent H(8)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(9)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. The corner-sharing octahedral tilt angles are 55°. In the seventh H site, H(7) is bonded to one Y(2), one Y(5), and two equivalent Y(4) atoms to form HY4 tetrahedra that share  a cornercorner with one H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(6)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra,  a cornercorner with one H(9)Y4 tetrahedra, corners with two equivalent H(10)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with three equivalent H(3)Y4 tetrahedra, corners with three equivalent H(5)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra, and  an edgeedge with one H(9)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the eighth H site, H(8) is bonded to one Y(1), one Y(2), one Y(3), and one Y(4) atom to form HY4 tetrahedra that share corners with two equivalent H(11)Y6 octahedra,  a cornercorner with one H(1)Y4 tetrahedra,  a cornercorner with one H(5)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra,  a cornercorner with one H(9)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(3)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with three equivalent H(10)Y4 tetrahedra, corners with three equivalent H(6)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra, and  an edgeedge with one H(9)Y4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the ninth H site, H(9) is bonded to one Y(1), one Y(3), one Y(4), and one Y(5) atom to form HY4 tetrahedra that share  a cornercorner with one H(10)Y4 tetrahedra,  a cornercorner with one H(7)Y4 tetrahedra,  a cornercorner with one H(8)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(2)Y4 tetrahedra, corners with two equivalent H(4)Y4 tetrahedra, corners with two equivalent H(5)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with three equivalent H(3)Y4 tetrahedra,  an edgeedge with one H(10)Y4 tetrahedra,  an edgeedge with one H(2)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(7)Y4 tetrahedra,  an edgeedge with one H(8)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. In the tenth H site, H(10) is bonded to one Y(1), one Y(2), one Y(3), and one Y(5) atom to form HY4 tetrahedra that share  a cornercorner with one H(3)Y4 tetrahedra,  a cornercorner with one H(4)Y4 tetrahedra,  a cornercorner with one H(5)Y4 tetrahedra,  a cornercorner with one H(9)Y4 tetrahedra, corners with two equivalent H(1)Y4 tetrahedra, corners with two equivalent H(6)Y4 tetrahedra, corners with two equivalent H(7)Y4 tetrahedra, corners with three equivalent H(2)Y4 tetrahedra, corners with three equivalent H(8)Y4 tetrahedra,  an edgeedge with one H(1)Y4 tetrahedra,  an edgeedge with one H(3)Y4 tetrahedra,  an edgeedge with one H(4)Y4 tetrahedra,  an edgeedge with one H(5)Y4 tetrahedra,  an edgeedge with one H(6)Y4 tetrahedra,  an edgeedge with one H(9)Y4 tetrahedra, and  a faceface with one H(11)Y6 octahedra. In the eleventh H site, H(11) is bonded to two equivalent Y(1), two equivalent Y(3), and two equivalent Y(5) atoms to form a mixture of corner and face-sharing HY6 octahedra. is represented by the CIF file [CIF]
data_Y10H21
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.367
_cell_length_b   7.349
_cell_length_c   8.205
_cell_angle_alpha   102.946
_cell_angle_beta   97.333
_cell_angle_gamma   106.859
_symmetry_Int_Tables_number   1
_cell_volume   350.350
_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
  Y  Y0  1  0.703  0.653  0.901  1.0
  Y  Y1  1  0.500  0.250  0.501  1.0
  Y  Y2  1  0.297  0.851  0.100  1.0
  Y  Y3  1  0.703  0.149  0.900  1.0
  Y  Y4  1  0.101  0.449  0.700  1.0
  Y  Y5  1  0.500  0.750  0.499  1.0
  Y  Y6  1  0.901  0.049  0.297  1.0
  Y  Y7  1  0.297  0.347  0.099  1.0
  Y  Y8  1  0.099  0.951  0.703  1.0
  Y  Y9  1  0.899  0.551  0.300  1.0
  H  H10  1  0.550  0.975  0.349  1.0
  H  H11  1  0.351  0.575  0.951  1.0
  H  H12  1  0.149  0.173  0.549  1.0
  H  H13  1  0.649  0.425  0.049  1.0
  H  H14  1  0.549  0.474  0.349  1.0
  H  H15  1  0.450  0.025  0.651  1.0
  H  H16  1  0.948  0.769  0.154  1.0
  H  H17  1  0.361  0.077  0.949  1.0
  H  H18  1  0.639  0.923  0.051  1.0
  H  H19  1  0.150  0.677  0.550  1.0
  H  H20  1  0.249  0.624  0.249  1.0
  H  H21  1  0.751  0.376  0.751  1.0
  H  H22  1  0.948  0.282  0.154  1.0
  H  H23  1  0.052  0.231  0.846  1.0
  H  H24  1  0.451  0.526  0.651  1.0
  H  H25  1  0.851  0.827  0.451  1.0
  H  H26  1  0.257  0.128  0.256  1.0
  H  H27  1  0.743  0.872  0.744  1.0
  H  H28  1  0.000  0.000  0.000  1.0
  H  H29  1  0.052  0.718  0.846  1.0
  H  H30  1  0.850  0.323  0.450  1.0
[/CIF]
.