TiO2 bulk structures

Figure 21 ALISS polar scans of a TiO2(110)-p(l x 1) surface taken along the (a) [001] direction and (b) [—110] direction using 1-keV Li" " ions backscattered at 160°. The solid circles are experimental data points and the solid curve is the result of theoretical calculations. Dotted lines demonstrate simulations for an error in critical angle by +1.0°. The dashed line shows the simulations for the bulk structure shown in Figure 20. (From Ref. 41.)...

Methanol decomposition on 114 -faceted TiO2(001) was accompanied by the formation of dimethyl ether attributed to the presence of four-coordinate Ti surface cations, yet no ether was formed on the vacuum annealed SnO2(110) surface, which also contains four-coordinate metal cations. However, the tin cations present on the surface are present as Sn SnO has a bulk four-coordinate structure, hence there is only one coordination vacancy, again precluding bimolecul lr coupling reactions [79]. 

The addition of a second oxide to the titania surface produces new nucleation sites for Au and improves the dispersion of the admetal. " In the CeO /TiOgCllO) systems, the Ce cations adopt a structural geometry (Fig. 6.2A) and an oxidation state (-1-3) which are quite different from those seen in bulk ceria or for ceria nanoparticles deposited on metal substrates. On TiO2(110), one has CegOg dimers that join forming wire-like structures on the terraces of the titania substrate. ... 

---