Apr 17 2013
Diamond is an allotrope of carbon wherein carbon atoms are arranged in the form of a diamond cube. Diamond is transparent to opaque due to its optical isotropic properties. As there is a strong covalent bonding within the crystal, diamond is a good thermal conductor, unlike most electrical insulators. The thermal conductivity of the diamond was determined to be five times more than copper. The high thermal conductance of diamond enables its use in semiconductor manufacture to suppress the overheating of silicon and other semiconductor materials.
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Applications
Applications of a diamond are listed below:
- Diamond is commonly used in jewelry as they are very beautiful and dazzle in the light. Diamonds are also very expensive.
- Synthetic diamonds are used in saws and drill bits to cut a range of materials.
- Cutting and polishing of other gemstones are also done using diamond.
- The fine engraving of materials is also possible using diamonds
- Diamonds are used in micro-bearings especially in watches.
- Diamonds can absorb a lot of heat. Hence they can be used in microelectronics for conducting heat away from heat-sensitive components of the electronics.
- Computer processors and microchips are normally coated in diamonds as they are semiconductors of electricity.
Chemical Properties
The chemical properties of diamond are provided in the table below:
| Chemical Properties |
| Chemical Formula |
C |
| Molecular Weight |
12.01 g |
| CAS No. |
7782-40-3 |
| IUPAC Name |
N/A |
| Group |
III-IV |
| Band Gap |
5.47 eV |
| Band Gap Type |
Indirect |
| Crystal Structure |
Diamond |
| Symmetry Group |
Oh7-Fd3m |
| Lattice Constant |
3.567 Angstroms |
Electrical Properties
The electrical properties of diamond are provided in the table below:
| Electrical Properties |
| Intrinsic Carrier Concentration |
10-27cm-3 |
| Electron Mobility |
≤ 2200 cm2 V-1 s-1 |
| Hole Mobility |
≤ 1800 cm2 V-1 s-1 |
| Electron Diffusion Coefficient |
≤ 57 cm2 s-1 |
| Hole Diffusion Coefficient |
≤ 46 cm2 s-1 |
| Electrical Resistivity |
46 Ωcm |
Thermal, Mechanical and Optical Properties
The thermal, mechanical, and optical properties of diamond are provided in the tables below:
| Mechanical Properties |
| Melting Point |
938.25 °C |
| Density |
3.515 g cm-3 |
| Young's Modulus |
1050 GPa |
| Shear Modulus |
478 GPa |
| Bulk Modulus |
442 GPa |
| Specific Heat (@ 298 K) |
0.52 J g-1 K-1 |
| Thermal Properties |
| Thermal Conductivity |
6-20 W cm-1 °C-1 |
| Thermal Diffusivity |
3-11 cm2 s-1 |
| Thermal Expansion Coefficient |
0.8x10-6 °C-1 |
| Optical Properties |
| Refractive Index |
2.4 |
| Radiative Recombination Coefficient (@ 300 K) |
9x105 cm3 s-1 |
Safety Information
| Safety Information |
| GHS Hazard Statements |
NA |
| Safety Precautions |
S 22,24,25 |