Excellent lectures by Dr Jeffrey C Grossman that describes the ideas behind X-ray really well. [[https://youtu.be/AqCz_b7VJK8?si=jPZq8In1ABTT4xnI][MIT 3.091 | 21. X-ray Diffraction Techniques I (Intro to Solid-State Chemistry)]] [[https://youtu.be/S1kqa_qGmHs?si=b8_KITp6ivQIpCQF][MIT 3.091 | 22. X-ray Diffraction Techniques II (Intro to Solid-State Chemistry)]] Copper K-α is an x-ray energy frequently used on labscale x-ray instruments. The energy is 8.04 keV, which corresponds to an x-ray wavelength of 1.5406 Å. This causes the prefactor in the scattering equation to be: k = 2 π λ = 4.0784 Å − 1 {\displaystyle k={\frac {2\pi }{\lambda }}=4.0784\,\mathrm {\AA} ^{-1}} X-Ray Diffraction A Practical Approach Authors: C. Suryanarayana , M. Grant Norton