Review Article

The Progress of T i O 𝟐 Nanocrystals Doped with Rare Earth Ions

Table 2

Proposed chemical structures of TNTs and their corresponding lattice parameters. Reprinted with permission from [32].

Chemical structureLattice parameters

Anatase TiO2Tetragonal; 𝑎 = 3 . 7 9  nm, 𝑏 = 3 . 7 9 , 𝑐 = 2 . 3 8
N2Ti3O7, Na2Ti3O7, NaxH2−x Ti3O7Monoclinic; 𝑎 = 1 . 9 2 6  nm, 𝑏 = 0 . 3 7 8 , 𝑐 = 0 . 3 0 0 , 𝛽 = 1 0 1 . 4 5
H2Ti2O4 (OH)2, Na2Ti2O4 (OH)2Orthorhombic; 𝑎 = 1 . 8 0 8  nm, 𝑏 = 0 . 3 7 9 , 𝑐 = 0 . 2 9 9
HxTi2−x/4  □x/4 O4 (H2O)Orthorhombic; 𝑎 = 0 . 3 7 8  nm, 𝑏 = 1 . 8 7 4 , 𝑐 = 0 . 2 9 8
H2Ti4O9 (H2O)Monoclinic; 𝑎 = 1 . 8 7 7  nm, 𝑏 = 0 . 3 7 5 , 𝑐 = 1 . 1 6 2 , 𝛽 = 1 0 4 . 6

□: Vacancy.