Figure 1.

Experimental set-up: a kapton capillary filled with a solution of silver NPs (face-centred-cubic). Bragg rings q₁₁₁ and q₂₀₀ are illustrated by circles on the detector plane. At least one of the exposed NPs happens to be oriented such that two reciprocal lattice (body-centred-cubic) peaks are intersecting the detector at q₁₁₁. Dashed lines represent the scattering vectors (separated by the angle ψ), and solid lines represent the projection of those vectors onto the detector plane (separated by the angle Δ). Artwork courtesy of Gregory M. Stewart (SLAC). (Online version in colour.)