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Traditional pure-carbon diamonds have a simple structure (tetrahedral, if I'm not mistaken). But common types of diamonds have other elements within them. For example, yellow diamond has nitrogen in it (at a rate of around 1 per million carbon atoms). My question is: what does the lattice structure look like with the occasional nitrogen atom thrown in the mix? The other one I'm curious about is blue diamonds, which have trace amounts of boron.

Ideally, I'd like to know what the structural/chemical formula might look like.

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    $\begingroup$ I assume it is very similar as for the group 13 and 15 dotting elements for P (holes) and N ( electrons) Si semiconductors, as Si has AFAIK the same structure. $\endgroup$
    – Poutnik
    May 26, 2022 at 7:33
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    $\begingroup$ It looks the same, only with N or B atoms instead of some C. $\endgroup$ May 26, 2022 at 15:50
  • $\begingroup$ The main difference is the extra valence electron of nitrogen. In a single site replacement, nitrogen will only form 3 bonds plus a lone pair, so one of the C-N bonds in broken, leaving an unpaired electron on a nearby carbon. $\endgroup$
    – Hayden S
    May 27, 2022 at 3:39

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Converting my comment into answer

Your query has been answered in this article. So I am going to write the relevant parts.

Nitrogen atoms are very small and have the ability to substitute for the carbon atoms in diamond's crystal structure. Trace amounts of nitrogen substituting for carbon in the diamond crystal lattice will cause the diamond crystal to selectively absorb blue light and selectively transmit yellow. This will cause those nitrogen-bearing diamonds to have a yellow color. Nitrogen is the most common impurity that substitutes for carbon and can comprise up to 1% of a diamond on the basis of mass.

Nitrogen can exist in the diamond crystal lattice in a number of ways. One way that influences color is when a single nitrogen atom is shared by four carbon tetrahedrons. This defect is known as the "C center" and is shown in the accompanying illustration. In this configuration, just one nitrogen atom per 100,000 carbon atoms can produce a noticeable yellow color in the crystal.

enter image description here

When nitrogen atoms substitute for carbon in the configuration described above, it produces a defect in the diamond crystal which alters how light passes through. The defect causes a selective absorption of blue light. The remainder of the spectrum is transmitted, and that results in the perception of yellow color in the eye of the observer.

Yellow color in mined diamonds can be also caused by the N3 defect. It consists of three nitrogen atoms clustered around a vacant carbon position in the diamond crystal lattice. When an N3 defect is accompanied by an N2 defect, certain wavelengths of blue and violet light are selectively absorbed by the diamond, and yellow light is selectively transmitted. This gives the diamond an apparent yellow color in the eye of the observer.

enter image description here

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