# Tag Info

## New answers tagged crystals

0

Referring to your figure: Each corner atom contribute, 1/18. Top, bottom, left and right atoms on the faces each contribute, 1/9. The closest and furthest atoms on the faces each contribute, 2/9. To calculate these numbers one needs to find angles which are nothing but 60 or 120 degrees.

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I'm guessing that the question is asking how you work out how many lattice points are in the cell. If so the standard procedure is to displace the cell a small distance along each of the lattice vectors than count the number of points the cell contains. I'll illustrate this in 2D since my abilities to draw convincing 3D diagrams are limited. Consider this ...

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Well, The FCC's (along with BCC's) are conventional unit cells, not primitive unit cells. As for the contribution of points, it is different for the corners and face centers. Each corner of a unit cell in a lattice is joined to 7 other unit cells. so the corner point is shared equally between 8 unit cells. Hence the corner contributes only $\frac{1}{8}$th of ...

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As far as I know, there is zero physics in "Crystal Energy", which if I understand what you mean, is related to Crystal Healing. There is a good bit of validity to the placebo effect and belief, so a person believing in something, whether the practitioner or the patient, can have an effect or the impression of an effect, but that's not physics either. ...

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Crystals have internal energy including some energy associated with molecular vibrations. Amorphous materials have internal energy including some energy associated with molecular vibrations. In addition to molecular vibrations, crystals can exhibit mechanical (macroscopic) vibrations. An example of a resonant macroscopic vibrator is a tuning fork. But, ...

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See, a crystal due to its temperature and through various media can be made to vibrate. Now because of the fact that the atoms(lattice points, could be molecules too) are connected with each other, the vibration actually spreads in all directions. Thus this vibration acts as an wave. But the whole of crystal, because of its structure can vibrate only in ...

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