X-ray Diffraction: Why X-rays Don't Diffract Easily

X-rays are electromagnetic radiation with very short wavelengths (0.01–10 nm) compared to visible light (400–700 nm).

Diffraction (wave spreading around obstacles) depends on wavelength and obstacle size. X-rays' short wavelength means they are not diffracted by most objects—openings/obstacles would need to be nanometers in size.

However, X-rays are diffracted by crystals because atomic spacing in crystals matches X-ray wavelengths. This property enables X-ray crystallography to determine crystal structures.