Titanium Di Oxide (Tio2)
Titanium dioxide, also known as titanium(IV) oxide or titania, is the naturally occurring oxide of titanium, chemical formula TiO2. When used as a pigment, it is called titanium white, Pigment White 6, or CI 77891. Generally it comes in two different forms, rutile and anatase. It has a wide range of applications, from paint to sunscreen to food colouring. When used as a food colouring, it has E number E171.
Occurrence
Titanium dioxide occurs in nature as well-known minerals rutile, anatase and brookite, and additionally as two high pressure forms, a monoclinic baddeleyite-like form and an orthorhombic a-PbO2-like form, both found recently at the Ries crater in Bavaria.[1][2] The most common form is rutile,[3] which is also the equilibrium phase at all temperatures.[4] The metastable anatase and brookite phases both convert to rutile upon heating.[3][5] Rutile, anatase and brookite all contain six coordinated titanium.
Titanium dioxide has eight modifications – in addition to rutile, anatase and brookite there are three metastable forms produced synthetically (monoclinic, tetragonal and orthorombic), and five high pressure forms (a-PbO2-like, baddeleyite-like, cotunnite-like, orthorhombic OI, and cubic phases):