X-ray crystal structures

What is the main reason crystals can diffract X-rays?

Because their atoms are arranged in a regular, ordered fashion.

What equation governs X-ray diffraction in crystals?

Bragg’s Law: 2dsin⁡θ = nλ

What scatters X-rays in a crystal structure?

The electron clouds around atoms.

Why are X-rays used instead of visible light in crystallography?

X-rays have a wavelength (~0.1 nm) comparable to atomic distances (~1.5 Å), allowing atomic-level resolution.

How many atoms per unit cell in FCC?

4 atoms

What is a unit cell?

The smallest repeating unit in a crystal lattice.

What are the three cubic unit cells?

Primitive Cubic (PC), Body-Centered Cubic (BCC), Face-Centered Cubic (FCC)

What is the significance of resolution in X-ray crystallography?

It determines the level of detail seen in the structure; lower Å = higher resolution.

dna was discovered using?

X-ray crystallography