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2.4 More complex structures

Oxides: Rutile (TiO )
2

Crystal data

Formula sum TiO 2
Crystal system tetragonal

Space group P 4 /m n m (no. 136)
2
Unit cell dimensions a = 4.5937 Å, c = 2.9587 Å Octahedra in Rutile

Z 2

Atomic coordinates

Atom Ox. Wyck. x y z

Ti1 +4 2a 0 0 0

O1 -2 4f 0.30469(9) 0.30469(9) 0

Structural features:
Structural features:
• no HCP arrangement of O (CN(O,O) = 11)
• mixed corner and edge sharing of TiO -octahedra
6
• columns of trans edge sharing TiO -octahedra,
6
connected by common corners
• many structural variants

• application: pigment