Difference between revisions of "Carbon"
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* 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) | ||
Revision as of 14:13, 1 June 2023
See: Gemstone like compound#Carbons versatility
sp3 allotropes:
- Diamond (cubic)
- Lonsdaleite (hexagonal)
- ...
- O16 carbon – orthorhombic superhard – all-sp3 6 membered rings
- Further less energetically stable all-sp3 allotropes: BC8, BC12, R16
sp2 allotropes:
- Buckyballs (convex curvature; concave from inside) – weak molecular solids
- Nanotubes (no curvature – flat rolled)
- 3D meshes (hyperbolic curvature)
- "penta graphene" (cairo pattern)
- ...
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)
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
