Yttrium titanate (pyrochlore) Y₂Ti₂O₇

Unit cell

Lattice constants

a = 10.099 Å, b = 10.099 Å, c = 10.099 Å; α = 90°, β = 90°, γ = 90°

Cell volume

1029.9 ų

Atoms in the cell

88 (Y 16, Ti 16, O 56)

Formula units Z

8

Calculated density

4.97 g cm⁻³

Shortest contact

1.940 Å

Coordination

Y

CN 2 at 2.19 Å (2 O)

Ti

CN 6 at 1.94 Å (6 O)

O

CN 2 at 1.94 Å (1.71 Ti + 0.57 Y)

About the structure

• A fluorite superstructure with one oxygen in eight removed in an ordered way: Ti⁴⁺ become six-coordinate (corner-sharing TiO₆ octahedra), Y³⁺ stay eight-coordinate in a distorted cube.
• The pyrochlore lattice of corner-sharing tetrahedra of A sites is geometrically frustrated — Ho₂Ti₂O₇ and Dy₂Ti₂O₇ on this framework are the "spin ice" materials.
• Coordinates from the Crystallography Open Database, entry 4030878 (open data); hydrogen and water sites with partial occupancy below 0.5 are left out.

Atom positions (fractional, one cell)

Z, coordination numbers, distances, density and packing on this page are computed from these coordinates.