Difference between revisions of "Carbon"
From apm
(corrected spelling of lonsdaleite, added O16 carbon and other sp3 allotropes) |
m (→Way harder than diamond) |
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'''sp<sup>3</sup> allotropes:''' | '''sp<sup>3</sup> allotropes:''' | ||
| − | * Diamond (cubic) | + | * [[Diamond]] (cubic) |
| − | * Lonsdaleite (hexagonal) | + | * [[Lonsdaleite]] (hexagonal) |
| + | * [[Dialondeite]] (only accessible via [[piezomechanosynthesis]]) | ||
* ... | * ... | ||
* O16 carbon – orthorhombic superhard – all-sp3 6 membered rings | * O16 carbon – orthorhombic superhard – all-sp3 6 membered rings | ||
| Line 11: | Line 12: | ||
'''sp<sup>2</sup> allotropes:''' | '''sp<sup>2</sup> allotropes:''' | ||
| + | * Graphite (today single cystalline graphite is called HOPG for highly ordered pyrolytic graphite) <br>Future: POPMG for "perfectly ordered piezomechanosynthesized graphite. | ||
* Buckyballs (convex curvature; concave from inside) – weak molecular solids | * Buckyballs (convex curvature; concave from inside) – weak molecular solids | ||
* Nanotubes (no curvature – flat rolled) | * Nanotubes (no curvature – flat rolled) | ||
* 3D meshes (hyperbolic curvature) | * 3D meshes (hyperbolic curvature) | ||
* "penta graphene" (cairo pattern) | * "penta graphene" (cairo pattern) | ||
| + | * ... | ||
| + | |||
| + | '''No exactly defined structure:''' | ||
| + | |||
| + | * DLC diamond like carbon – [https://en.wikipedia.org/wiki/Diamond-like_carbon wikipedia] | ||
| + | * Glassy carbon – [https://en.wikipedia.org/wiki/Glassy_carbon wikipedia] | ||
| + | * Other form of amorphous carbon – [https://en.wikipedia.org/wiki/Amorphous_carbon wikipedia] | ||
* ... | * ... | ||
| Line 23: | Line 32: | ||
'''Binary compounds:''' | '''Binary compounds:''' | ||
* Silicon carbide SiC aka moissanite | * Silicon carbide SiC aka moissanite | ||
| − | * | + | * Carbon nitrides: [[beta carbon nitride]] and cubic gauche carbon nitride |
---- | ---- | ||
* Titanium carbide TiC aka titanium-khamrabaevite (cubic rock salt structure) Mohs 9-9.5 [[refractory]] | * Titanium carbide TiC aka titanium-khamrabaevite (cubic rock salt structure) Mohs 9-9.5 [[refractory]] | ||
| Line 41: | Line 50: | ||
* Aluminium carbide [https://en.wikipedia.org/wiki/Aluminium_carbide] (reacts with water - releases methane gas CH<sub>4</sub>) | * Aluminium carbide [https://en.wikipedia.org/wiki/Aluminium_carbide] (reacts with water - releases methane gas CH<sub>4</sub>) | ||
* <small>Beryllium carbide [https://en.wikipedia.org/wiki/Beryllium_carbide Be<sub>2</sub>C] (very hard but reactive, toxic and rare)</small> | * <small>Beryllium carbide [https://en.wikipedia.org/wiki/Beryllium_carbide Be<sub>2</sub>C] (very hard but reactive, toxic and rare)</small> | ||
| − | * Magnesium carbide ??? | + | * Magnesium carbide ??? - magnesium acetylide Mg<sub>2</sub>C<sub>3</sub> [https://de.wikipedia.org/wiki/Magnesiumcarbid (de wikipedia)] |
* Calcium carbide [https://en.wikipedia.org/wiki/Calcium_carbide CaC<sub>2</sub>] (an [https://en.wikipedia.org/wiki/Category:Acetylides acetylide] - reacts with water - releases ethyne gas C<sub>2</sub>H<sub>2</sub>) | * Calcium carbide [https://en.wikipedia.org/wiki/Calcium_carbide CaC<sub>2</sub>] (an [https://en.wikipedia.org/wiki/Category:Acetylides acetylide] - reacts with water - releases ethyne gas C<sub>2</sub>H<sub>2</sub>) | ||
* TODO: La, Ce, (Li, Na, K) | * TODO: La, Ce, (Li, Na, K) | ||
| + | |||
| + | == Way harder than diamond == | ||
| + | |||
| + | Macroscopic (pre)tensions can increase resilience but not ultimate tensile strength. <br> | ||
| + | In glass there internal tensions can increase resilience massively. <br> | ||
| + | See Wikipedia on: [https://en.wikipedia.org/wiki/Prince_Rupert%27s_drop Prince Rupert's drop]s <br> | ||
| + | These drops have their tail as weak spot and their shape is pre-given so they are of not much use beside a curiosity for sci-education. <br> | ||
| + | In principle using advanced bottom up manufacturing it might be possible to toughen diamond a lot via internal tensions but leaving no weak spot. | ||
== Related == | == Related == | ||
Latest revision as of 15:33, 1 June 2023
See: Gemstone like compound#Carbons versatility
sp3 allotropes:
- Diamond (cubic)
- Lonsdaleite (hexagonal)
- Dialondeite (only accessible via piezomechanosynthesis)
- ...
- O16 carbon – orthorhombic superhard – all-sp3 6 membered rings
- Further less energetically stable all-sp3 allotropes: BC8, BC12, R16
sp2 allotropes:
- Graphite (today single cystalline graphite is called HOPG for highly ordered pyrolytic graphite)
Future: POPMG for "perfectly ordered piezomechanosynthesized graphite. - Buckyballs (convex curvature; concave from inside) – weak molecular solids
- Nanotubes (no curvature – flat rolled)
- 3D meshes (hyperbolic curvature)
- "penta graphene" (cairo pattern)
- ...
No exactly defined structure:
- DLC diamond like carbon – wikipedia
- Glassy carbon – wikipedia
- Other form of amorphous carbon – wikipedia
- ...
Exotic allotropes:
- ...
Binary compounds:
- Silicon carbide SiC aka moissanite
- Carbon nitrides: beta carbon nitride and cubic gauche carbon nitride
- Titanium carbide TiC aka titanium-khamrabaevite (cubic rock salt structure) Mohs 9-9.5 refractory
- Vanadium carbide VC (vanadium is not too common) vanadium-khamrabaevite
similar is: NbC and TaC (Nb is not abundant, Ta is extremely rare) - Zirconium cabide ZrC [1] (same structure but no natural mineral present)
similar is: HfC (Hf is pretty rare) - Iron carbide (this here is not cementite!!) iron-khamrabaevite (unknown stability, likely very hard)
- Chromium_carbide (various stoichiometric & structures - may point to useful covalent behavior)
Cr3C2 Tongbaite (refractory, Mohs 9.6; orthorhombic; 6.64g/ccm) Cr is not too abundant
Cr23C6 - Molybdenium carbide (de) Mo2C (insoluble, two modifications α and β) Mo is rather rare
- Tungsten_carbide (hexagonal, Mohs 9) W is rather rare
- Fe3C, Ni3C, Co3C cohenite endmembers (likely rather metallic, Mohs 5.5-6)
- copper and zinc are more electronegative => more covalent behavior => organometallic compounds
- Boron carbide B4C [2] (boron is not too common)
- Aluminium carbide [3] (reacts with water - releases methane gas CH4)
- Beryllium carbide Be2C (very hard but reactive, toxic and rare)
- Magnesium carbide ??? - magnesium acetylide Mg2C3 (de wikipedia)
- Calcium carbide CaC2 (an acetylide - reacts with water - releases ethyne gas C2H2)
- TODO: La, Ce, (Li, Na, K)
Way harder than diamond
Macroscopic (pre)tensions can increase resilience but not ultimate tensile strength.
In glass there internal tensions can increase resilience massively.
See Wikipedia on: Prince Rupert's drops
These drops have their tail as weak spot and their shape is pre-given so they are of not much use beside a curiosity for sci-education.
In principle using advanced bottom up manufacturing it might be possible to toughen diamond a lot via internal tensions but leaving no weak spot.
Related
- Diamondoid
- Diamond
- Elements in the same group: Carbon, Silicon, Germanium, Tin, Lead
- Chemical element
External links
- Wikipedia: Pi bond
- Wikipedia: Orbital hybridisation
- Wikipedia: Carbides and Category:Carbides
- Wikipedia: Graphite_intercalation_compound KC8
- Wikipedia: Metal_carbido_complex (Transition metal carbides)
- Wikipedia: Metallocarbohedryne
