atomic patterns in crystals

Spiral growth pattern in a Vietnamese pink sapphire.

Occasionally, we find a gem inclusion that uncovers the crystal structure and growth pattern of the host gem. These spirals start at an inhomogeneity in the lattice, such as an enclosed crystal or twinning plane. Each twist in the spiral records another stage of growth in the crystal, revealing the pattern in which the atoms organised themselves during crystallisation.

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quickdraw-exposure  asked:

Hey! I really liked your post on the double slit experiment, but you didn't mention my favorite part: it also works with electrons, something we normally think of as particles! Even cooler, if you only shoot one electron at a time through the slits, you also get a diffraction pattern! But, if you have a detector to see which of the two slits the electron moves through, you only get the two lines you would get from a particle, showing that electrons behave differently if you're looking at them!

This is very true, and very cool! French physicist Louis de Broglie first suggested that not only do photons have wave-particle duality, but ALL particles do.

The Davisson-Germer experiment  confirmed de Broglie’s claim: electrons were fired at a nickel crystal, and after hitting it, they scattered to form an electron diffraction pattern—the evenly-spaced atoms of the crystal acted like a diffraction grating. This pattern was compared to the diffraction patterns of x-rays on crystal, and electrons were thus shown to exhibit a wave behaviour.

de Broglie also devised a way to assign wavelengths to particles like electrons, protons and neutrons, using their momentum (λ=h/p).

Pretty rad!