A clean diamond is composed solely of carbon. However, diamond crystals often contain certain amounts of trace elements, which take place in some of the carbon atoms, especially those of nitrogen. Diamond can be divided into two types of diamonds, as nitrogen is present in large quantities or not in the crystal structure of coal.
- Type 1 diamonds contain nitrogen atoms as the main impurity (up to 0.2%).
- Diamond Type 2 does not contain substantial nitrogen pollution.
The majority of all natural diamonds are type 1A. The nitrogen in these diamonds is present as aggregates of two, three and four atoms. Diamonds 1AA nitrogen present as aggregates two nitrogen atoms. 1AB type of nitrogen present as aggregates of diamonds four nitrogen atoms in the workplace. Type 1 aa / B contain both A and B forms of nitrogen. A and B aggregates cause absorption in the infrared spectrum, but do not affect the color.
Type 1a, with four nitrate collected
Type 1AB, the nitrogen atom next to the vacancy
Generally, diamonds contain B also contain aggregates of aggregates of three nitrogen atoms. This is called color center N3 (N for "physical" is not nitrogen). N3 color centers give rise to the N2 and N3 absorption, affecting the blue-violet region of the visible spectrum. These absorption are responsible for a series of Cape diamonds known. Upson yellow saturation power depends on N2 and N3 absorption. N3 is characterized by the color of the center line at 415 nm (absorption of the N3), more peaks between 415 and 478nm (absorption N2) and ethernet broadband in the ultraviolet. Under the hand spectroscope 415 nm line may be visible. However, sometimes diamond cooling is necessary to absorb all the properties.
Line 415 nm should be regarded as a bluff, the series
Type 1b
Any nitrogen present in the diamond type 1B is that the individual atoms replace carbon atoms at random in the crystal structure of coal. The resulting surplus elevtion merger led to the absorption of blue light, which causes a yellow color. Higher concentration of nitrogen, the darker yellow. Golden yellow color is also possible, traditionally called "canary yellow.
Type 1b, isolated nitrogen atom substitution (red)
Type 1b stones absorb the blue part of the visible spectrum and may have a small absorption peaks at 503 nm and 637 nm. The main feature of type 1b diamond characteristic infrared absorption band at 1130 cm-1 and the line marked to 1344 cm-1.
Type 2A
Type 2a diamonds are rare and occur in nature as an irregular shape, and not with a clear face. Type 2a diamonds are almosr pure, containing small amounts of nitrogen. They are excellent conductors of heat.
Type 2a diamonds that do not contain vacancies or lattice deformation of the crystals are colorless. Start Cullinan diamonds and Sierra Leone are examples of the type 2a diamonds.
Type 2b
Type 2b diamonds contain boron atoms as a main component of pollution. 2b type natural diamonds, the boron concentration is only about 0.5 parts per million (0.5 ppm). Boron exists as atoms replace carbon atoms at random in the crystal structure of diamond.
Type 2b, the boron atoms (green) replaces a carbon atom
Boron atoms have one electron less than carbon atoms, the shortage of energy is absorbed wavelengths, visible or red end of the spectrum. The absorption of this type 2b gives diamonds their color blue. Hope Diamond is one of the most famous diamonds known typw 2b diamond.
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