SOME PROPERTIES OF CARBON
Diamond | Graphite | C60 | |
Crystal Structure | cubic | hex. | fcc |
density (g cm-3) | 3.30 | 2.27 | 1.65 |
Lattice constant (A) | 3.513 | a=2.456 | 14.15 |
- | b=6.696 | - | |
C-C length (A) | 1.54 | 1.42 | 1.455 |
C=C length | - | - | 1.391 |
Standard heats of formation (k cal mol-1) | 0.4 | 0.0 | 9.08 |
bulk modulus (G Pa) | 1200 | 207 | 18(174) |
melting point (K) | 3700 | 3800 | sublm. 800 |
index of refraction | 2.42 | - | 2.2 (600nm) |
conductivity | insulator | conductor | semi conductor |
resistivity (ohm m) | 1 x 10E18 | 1.37 x 10E-5 | 1 x 10E14 (room temp) |
naturally occuring deposit | kimberlite | pegmatite | shungite |
location | S. Africa | Sri-Lanka | Russia |
crystal formation | octahedral | tubular | hexagonal, cubic |
name meaning | 'invincible' | 'to write' | named after arcitect |
Isothermal volume compressibilities (cm2 dyn-1) | 0.18 x 10E-12 | 2.7 x 10E-12 | 6.9 x 10E-12 |
Further properties of Buckminsterfullerene
C - C length (gas phase) | 1.458 Å |
C = C | 1.410 Å |
Cage Diameter | 7.11 Å |
C60 - C60 nearest approach | 3.1 Å |
Ionisation Potentials | |
C60 to C60+ | 7.6 ± 0.2 eV |
C60+ to C60 2+ | 12.25 ± 0.5 eV |
C602+ to C60 3+ | 17.0 ± 0.7 eV |
C60 3+ to C60 4+ | 21.7 eV by extrapolation |
Electron affinity | 2.6 eV |
Band Gap | 1.8 eV |
relative permitivity | 4.4 ± 0.2 |
absorption coefficients | 6.07 x 10E5 cm-1 @ 220 nm |
(thin film) | 1.21 x 10E5 cm-1 @ 442 nm |
2nd order polarizability | Zero (centrosymmetric) |
3rd order polarizability | 7.5 (± 2) x 10E-34 esu. |
13C NMR Chemical shift | 142.68 ppm |
Vapour pressure at 800K | 8.1 x 10E-4 Torr |
Entropy of sublimation at 700 K | 181.4 ± 2.3 kJ mol-1 |
Solubility (at 303 K) | |
carbon tetrechloride | 0.45 mg ml-1 |
benzene | 1.44 mg ml-1 |
toluene | 2.15 mg ml-1 |
carbon disulphide | 5.16 mg ml-1 |
hexane | 0.04 mg ml-1 |
SUPERCONDUCTING PROPERTIES OF FULLERENE COMPOUNDS
Superconducting Tc | |
K3C60 | 19 K |
Rb3C60 | 29 K |
Cs3C60 | 30 K |
Cs2RbC60 | 33 K |
Rb2.7Tl2.2C60 | 42.5 K* |
C60Ba6 | 7 K |
(* later withdrawn) |
SPECTROSCOPIC DATA
Rotational constant
0.0028 cm-1
IR active bands - four T1u
solid* | Gas phase | Ar matrix | |
(cm-1) | 1429.0 | 1406.9 | 1431.9 |
1182.5 | 1169.1 | 1184.8 | |
576.5 | 570.3 | 579.3 | |
527.0 | 527.0 | 530.0 | |
(micro m) | 6.998 | 7.108 | 6.984 |
8.456 | 8.554 | 8.440 | |
17.35 | 17.53 | 17.26 | |
18.87 | 18.98 | 18.87 |
UV and visible bands (hexane)
nm | cm-1 | log emax | eV |
211.0 | 47393 | 5.20 | 5.88 |
227.4 | 43975 | 4.95 | 5.46 |
256.6 | 38971 | 5.24 | 4.83 |
328.4 | 30451 | 4.72 | 3.78 |
377.0 | 26525 | 3.79 | 3.29 |
404.0 | 24754 | 3.47 | 3.07 |
Also detected are bands assigned to the ions;
C60+ at 973 nm and C60- at 1068 nm.
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