X-ray Crystallography
A technique that determines the three-dimensional atomic structure of a crystal from its X-ray diffraction pattern.
Formula / equation
nλ = 2d sin θ
Unit
pm
In depth
X-rays scattered by the regularly spaced atoms interfere constructively only at angles satisfying Bragg's law, and the resulting pattern of spots is mathematically inverted to give an electron density map. It provides bond lengths and angles more precisely than any other method.
Examples in the real world
The determination of the DNA double helix and of countless protein structures and drug–target complexes.