Difference between revisions of "Silicon"
From apm
m |
m (→Silicon dioxide SiO2) |
||
| Line 15: | Line 15: | ||
* [https://en.wikipedia.org/wiki/Tridymite Tridymite] (Mohs 7 | density 2.25–2.28 g/cm<sup>3</sup>) there are seven crystal phases of tridymite <br> two hexagonal: HP (β) & LHP -- three orthorhombic: OC (α) & OS & OP -- two monoclinic: MC & MX | * [https://en.wikipedia.org/wiki/Tridymite Tridymite] (Mohs 7 | density 2.25–2.28 g/cm<sup>3</sup>) there are seven crystal phases of tridymite <br> two hexagonal: HP (β) & LHP -- three orthorhombic: OC (α) & OS & OP -- two monoclinic: MC & MX | ||
* [https://en.wikipedia.org/wiki/Moganite Moganite] (not Mo'''R'''ganite!) (Mohs 6 | 2.52-2.58 g/cm<sup>3</sup> | monoclinic) | * [https://en.wikipedia.org/wiki/Moganite Moganite] (not Mo'''R'''ganite!) (Mohs 6 | 2.52-2.58 g/cm<sup>3</sup> | monoclinic) | ||
| + | |||
| + | Related: [[Binary diamondoid compound]] | ||
Revision as of 17:51, 9 December 2016
Silicon dioxide SiO2
Beside the commonly known quartz and amorphous glass there are many polymorphs of silicon dioxide (tectosilicates).
- Quartz (Mohs 7 by definition | density 2.65 g/cm3)
α-quartz: trigonal -- β-quartz: hexagonal
- Stishovite (Mohs 9-9.5 | density 4.287 g/cm3 | tetragonal - resembles rutile TiO2)
- Seifertite (Mohs ~9 | density 4.294 g/cm3 | orthorhombic - resembles scrutinyite α-PbO2)
- Coesite (Mohs 7.5 | density 2.92 g/cm3 (calculated) | monoclinic)
- Cristobalite (Mohs 6-7 | density 2.32–2.36 g/cm3)
α-Cristobalite tetragonal
β-Cristobalite cubic - resembles diamond / ZnS
- Tridymite (Mohs 7 | density 2.25–2.28 g/cm3) there are seven crystal phases of tridymite
two hexagonal: HP (β) & LHP -- three orthorhombic: OC (α) & OS & OP -- two monoclinic: MC & MX - Moganite (not MoRganite!) (Mohs 6 | 2.52-2.58 g/cm3 | monoclinic)
Related: Binary diamondoid compound
