Lecturw 18 (Carbon Allotropes, Graphite, Fullerenes, etc.) Flashcards
1
Q
What does metastable mean for forms of carbon?
A
it is thermodynamically unstable at room temperature with respect to the conversion to graphite, the conversion is very slow
2
Q
How do you synthesize C graphite into C diamond?
A
The High Pressure High Temperature process (HPHT)
3
Q
What is the structure of diamond?
A
- 3D covalent network of tetrahedral, sp3 hybridized C
- Electrical insulator
- High thermal conductivity
- Impurities: N, B, and H
4
Q
What is the structure of graphite?
A
- bidimensional layers of sp2 hybridized C
- very weak inter-layer interactions, facile sliding of layers against each other (cleavage)
5
Q
Staggered sheet structure meaning?
A
successive planes do not overlap perfectly
6
Q
What does turbostratic disorder mean?
A
the layers are parallel, but displaced and rotated with respect to each other
7
Q
What types of compounds form when graphite reacts with alkali metals?
A
Intercalation compounds
