![]()
出典:Wiktionary
From Brooke + -ite, named in 1825 for English crystallographer Henry James Brooke.
brookite (countable かつ uncountable, 複数形 brookites)
出典:Wikipedia
出典:『Wikipedia』 (2011/05/10 08:43 UTC 版)
Brookite is orthorhombic, and one of the four naturally occurring polymorphs (minerals with the same composition but different structure) of titanium dioxide, TiO2, approved by the International Mineralogical Association (IMA). The others are akaogiite (monoclinic), anatase (tetragonal) and rutile (tetragonal). Brookite is rare compared to anatase and rutile and, like these forms, it exhibits photocatalytic activity. Brookite has a larger cell volume than either anatase or rutile, with 8 TiO2 groups per unit cell, compared with 4 for anatase and 2 for rutile. Iron Fe, tantalum Ta and niobium Nb are common impurities.