The crystal structure described by HfZrO4 crystallizes in the monoclinic Cm space group. There are three inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a distorted body-centered cubic geometry to one O(12), one O(5), one O(6), one O(8), two equivalent O(3), and two equivalent O(9) atoms. In the second Hf site, Hf(2) is bonded in a body-centered cubic geometry to one O(1), one O(11), one O(12), one O(2), one O(3), one O(5), one O(7), and one O(9) atom. In the third Hf site, Hf(3) is bonded in a body-centered cubic geometry to one O(12), one O(5), one O(6), one O(8), two equivalent O(1), and two equivalent O(7) atoms. There are three inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a body-centered cubic geometry to one O(1), one O(10), one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. In the second Zr site, Zr(2) is bonded in a distorted body-centered cubic geometry to one O(10), one O(11), one O(2), one O(4), two equivalent O(1), and two equivalent O(7) atoms. In the third Zr site, Zr(3) is bonded in a body-centered cubic geometry to one O(10), one O(11), one O(2), one O(4), two equivalent O(3), and two equivalent O(9) atoms. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Hf(2), one Hf(3), one Zr(1), and one Zr(2) atom to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(1)Hf2Zr2 tetrahedra, corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with two equivalent O(9)Hf2Zr2 tetrahedra, corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(3)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra,  an edgeedge with one O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra, and  an edgeedge with one O(10)Zr4 tetrahedra. In the second O site, O(2) is bonded to two equivalent Hf(2), one Zr(2), and one Zr(3) atom to form OHf2Zr2 tetrahedra that share corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(11)Hf2Zr2 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra,  an edgeedge with one O(4)Zr4 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. In the third O site, O(3) is bonded to one Hf(1), one Hf(2), one Zr(1), and one Zr(3) atom to form OHf2Zr2 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(3)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with two equivalent O(7)Hf2Zr2 tetrahedra, corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(1)Hf2Zr2 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra,  an edgeedge with one O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra, and  an edgeedge with one O(4)Zr4 tetrahedra. In the fourth O site, O(4) is bonded to one Zr(2), one Zr(3), and two equivalent Zr(1) atoms to form distorted OZr4 tetrahedra that share corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra, corners with four equivalent O(10)Zr4 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the fifth O site, O(5) is bonded to one Hf(1), one Hf(3), and two equivalent Hf(2) atoms to form distorted OHf4 tetrahedra that share corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra, corners with four equivalent O(12)Hf4 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the sixth O site, O(6) is bonded to one Hf(1), one Hf(3), and two equivalent Zr(1) atoms to form OHf2Zr2 tetrahedra that share corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra, corners with four equivalent O(8)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra,  an edgeedge with one O(4)Zr4 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. In the seventh O site, O(7) is bonded to one Hf(2), one Hf(3), one Zr(1), and one Zr(2) atom to form OHf2Zr2 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(3)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with two equivalent O(7)Hf2Zr2 tetrahedra, corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra,  an edgeedge with one O(1)Hf2Zr2 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra,  an edgeedge with one O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra, and  an edgeedge with one O(4)Zr4 tetrahedra. In the eighth O site, O(8) is bonded to one Hf(1), one Hf(3), and two equivalent Zr(1) atoms to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(6)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra,  an edgeedge with one O(10)Zr4 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the ninth O site, O(9) is bonded to one Hf(1), one Hf(2), one Zr(1), and one Zr(3) atom to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(1)Hf2Zr2 tetrahedra, corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with two equivalent O(9)Hf2Zr2 tetrahedra, corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(3)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra,  an edgeedge with one O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra, and  an edgeedge with one O(10)Zr4 tetrahedra. In the tenth O site, O(10) is bonded to one Zr(2), one Zr(3), and two equivalent Zr(1) atoms to form OZr4 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra, corners with four equivalent O(4)Zr4 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. In the eleventh O site, O(11) is bonded to two equivalent Hf(2), one Zr(2), and one Zr(3) atom to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(2)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra,  an edgeedge with one O(10)Zr4 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the twelfth O site, O(12) is bonded to one Hf(1), one Hf(3), and two equivalent Hf(2) atoms to form OHf4 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra, corners with four equivalent O(5)Hf4 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. is represented by the CIF card [CIF]
data_HfZrO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.278
_cell_length_b   7.278
_cell_length_c   7.244
_cell_angle_alpha   60.181
_cell_angle_beta   60.181
_cell_angle_gamma   59.697
_symmetry_Int_Tables_number   1
_cell_volume   271.399
_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
  Hf  Hf0  1  0.136  0.136  0.622  1.0
  Hf  Hf1  1  0.636  0.135  0.123  1.0
  Hf  Hf2  1  0.135  0.636  0.123  1.0
  Hf  Hf3  1  0.135  0.135  0.124  1.0
  Zr  Zr4  1  0.133  0.635  0.626  1.0
  Zr  Zr5  1  0.634  0.634  0.127  1.0
  Zr  Zr6  1  0.635  0.635  0.625  1.0
  Zr  Zr7  1  0.635  0.133  0.626  1.0
  O  O8  1  0.053  0.505  0.984  1.0
  O  O9  1  0.745  0.745  0.250  1.0
  O  O10  1  0.260  0.794  0.733  1.0
  O  O11  1  0.492  0.492  0.537  1.0
  O  O12  1  0.989  0.989  0.044  1.0
  O  O13  1  0.240  0.240  0.756  1.0
  O  O14  1  0.766  0.289  0.226  1.0
  O  O15  1  0.993  0.993  0.495  1.0
  O  O16  1  0.010  0.548  0.476  1.0
  O  O17  1  0.743  0.743  0.779  1.0
  O  O18  1  0.289  0.766  0.226  1.0
  O  O19  1  0.489  0.489  1.000  1.0
  O  O20  1  0.242  0.242  0.281  1.0
  O  O21  1  0.794  0.260  0.733  1.0
  O  O22  1  0.505  0.053  0.984  1.0
  O  O23  1  0.548  0.010  0.476  1.0
[/CIF]
.
The crystal structure described by HfZrO4 crystallizes in the monoclinic Cm space group. There are three inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a distorted body-centered cubic geometry to one O(12), one O(5), one O(6), one O(8), two equivalent O(3), and two equivalent O(9) atoms. In the second Hf site, Hf(2) is bonded in a body-centered cubic geometry to one O(1), one O(11), one O(12), one O(2), one O(3), one O(5), one O(7), and one O(9) atom. In the third Hf site, Hf(3) is bonded in a body-centered cubic geometry to one O(12), one O(5), one O(6), one O(8), two equivalent O(1), and two equivalent O(7) atoms. There are three inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a body-centered cubic geometry to one O(1), one O(10), one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. In the second Zr site, Zr(2) is bonded in a distorted body-centered cubic geometry to one O(10), one O(11), one O(2), one O(4), two equivalent O(1), and two equivalent O(7) atoms. In the third Zr site, Zr(3) is bonded in a body-centered cubic geometry to one O(10), one O(11), one O(2), one O(4), two equivalent O(3), and two equivalent O(9) atoms. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Hf(2), one Hf(3), one Zr(1), and one Zr(2) atom to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(1)Hf2Zr2 tetrahedra, corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with two equivalent O(9)Hf2Zr2 tetrahedra, corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(3)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra,  an edgeedge with one O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra, and  an edgeedge with one O(10)Zr4 tetrahedra. In the second O site, O(2) is bonded to two equivalent Hf(2), one Zr(2), and one Zr(3) atom to form OHf2Zr2 tetrahedra that share corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(11)Hf2Zr2 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra,  an edgeedge with one O(4)Zr4 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. In the third O site, O(3) is bonded to one Hf(1), one Hf(2), one Zr(1), and one Zr(3) atom to form OHf2Zr2 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(3)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with two equivalent O(7)Hf2Zr2 tetrahedra, corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(1)Hf2Zr2 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra,  an edgeedge with one O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra, and  an edgeedge with one O(4)Zr4 tetrahedra. In the fourth O site, O(4) is bonded to one Zr(2), one Zr(3), and two equivalent Zr(1) atoms to form distorted OZr4 tetrahedra that share corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra, corners with four equivalent O(10)Zr4 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the fifth O site, O(5) is bonded to one Hf(1), one Hf(3), and two equivalent Hf(2) atoms to form distorted OHf4 tetrahedra that share corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra, corners with four equivalent O(12)Hf4 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the sixth O site, O(6) is bonded to one Hf(1), one Hf(3), and two equivalent Zr(1) atoms to form OHf2Zr2 tetrahedra that share corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra, corners with four equivalent O(8)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra,  an edgeedge with one O(4)Zr4 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. In the seventh O site, O(7) is bonded to one Hf(2), one Hf(3), one Zr(1), and one Zr(2) atom to form OHf2Zr2 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(3)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with two equivalent O(7)Hf2Zr2 tetrahedra, corners with two equivalent O(12)Hf4 tetrahedra, corners with two equivalent O(10)Zr4 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra,  an edgeedge with one O(1)Hf2Zr2 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra,  an edgeedge with one O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(5)Hf4 tetrahedra, and  an edgeedge with one O(4)Zr4 tetrahedra. In the eighth O site, O(8) is bonded to one Hf(1), one Hf(3), and two equivalent Zr(1) atoms to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(6)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra,  an edgeedge with one O(10)Zr4 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the ninth O site, O(9) is bonded to one Hf(1), one Hf(2), one Zr(1), and one Zr(3) atom to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(1)Hf2Zr2 tetrahedra, corners with two equivalent O(11)Hf2Zr2 tetrahedra, corners with two equivalent O(8)Hf2Zr2 tetrahedra, corners with two equivalent O(9)Hf2Zr2 tetrahedra, corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra,  an edgeedge with one O(2)Hf2Zr2 tetrahedra,  an edgeedge with one O(3)Hf2Zr2 tetrahedra,  an edgeedge with one O(6)Hf2Zr2 tetrahedra,  an edgeedge with one O(7)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra, and  an edgeedge with one O(10)Zr4 tetrahedra. In the tenth O site, O(10) is bonded to one Zr(2), one Zr(3), and two equivalent Zr(1) atoms to form OZr4 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra, corners with four equivalent O(4)Zr4 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. In the eleventh O site, O(11) is bonded to two equivalent Hf(2), one Zr(2), and one Zr(3) atom to form distorted OHf2Zr2 tetrahedra that share corners with two equivalent O(5)Hf4 tetrahedra, corners with two equivalent O(4)Zr4 tetrahedra, corners with four equivalent O(1)Hf2Zr2 tetrahedra, corners with four equivalent O(2)Hf2Zr2 tetrahedra, corners with four equivalent O(9)Hf2Zr2 tetrahedra,  an edgeedge with one O(12)Hf4 tetrahedra,  an edgeedge with one O(10)Zr4 tetrahedra, edges with two equivalent O(3)Hf2Zr2 tetrahedra, and edges with two equivalent O(7)Hf2Zr2 tetrahedra. In the twelfth O site, O(12) is bonded to one Hf(1), one Hf(3), and two equivalent Hf(2) atoms to form OHf4 tetrahedra that share corners with two equivalent O(2)Hf2Zr2 tetrahedra, corners with two equivalent O(6)Hf2Zr2 tetrahedra, corners with four equivalent O(3)Hf2Zr2 tetrahedra, corners with four equivalent O(7)Hf2Zr2 tetrahedra, corners with four equivalent O(5)Hf4 tetrahedra,  an edgeedge with one O(11)Hf2Zr2 tetrahedra,  an edgeedge with one O(8)Hf2Zr2 tetrahedra, edges with two equivalent O(1)Hf2Zr2 tetrahedra, and edges with two equivalent O(9)Hf2Zr2 tetrahedra. is represented by the CIF card [CIF]
data_HfZrO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.278
_cell_length_b   7.278
_cell_length_c   7.244
_cell_angle_alpha   60.181
_cell_angle_beta   60.181
_cell_angle_gamma   59.697
_symmetry_Int_Tables_number   1
_cell_volume   271.399
_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
  Hf  Hf0  1  0.136  0.136  0.622  1.0
  Hf  Hf1  1  0.636  0.135  0.123  1.0
  Hf  Hf2  1  0.135  0.636  0.123  1.0
  Hf  Hf3  1  0.135  0.135  0.124  1.0
  Zr  Zr4  1  0.133  0.635  0.626  1.0
  Zr  Zr5  1  0.634  0.634  0.127  1.0
  Zr  Zr6  1  0.635  0.635  0.625  1.0
  Zr  Zr7  1  0.635  0.133  0.626  1.0
  O  O8  1  0.053  0.505  0.984  1.0
  O  O9  1  0.745  0.745  0.250  1.0
  O  O10  1  0.260  0.794  0.733  1.0
  O  O11  1  0.492  0.492  0.537  1.0
  O  O12  1  0.989  0.989  0.044  1.0
  O  O13  1  0.240  0.240  0.756  1.0
  O  O14  1  0.766  0.289  0.226  1.0
  O  O15  1  0.993  0.993  0.495  1.0
  O  O16  1  0.010  0.548  0.476  1.0
  O  O17  1  0.743  0.743  0.779  1.0
  O  O18  1  0.289  0.766  0.226  1.0
  O  O19  1  0.489  0.489  1.000  1.0
  O  O20  1  0.242  0.242  0.281  1.0
  O  O21  1  0.794  0.260  0.733  1.0
  O  O22  1  0.505  0.053  0.984  1.0
  O  O23  1  0.548  0.010  0.476  1.0
[/CIF]
.