Smallest repeating parallelepiped that, when tiled through space, reproduces the full crystal. Specified by six lattice parameters (a, b, c, α, β, γ). The conventional unit cell may differ from the primitive unit cell for centred lattices.
Unit cell
Related concepts
- Crystal structure
- X-ray diffraction pattern
- Bragg diffraction: n λ = 2 d sin θ (Bragg & Bragg 1913)
- Madelung sum: M = Σ_shells (±n_k / r_k) for ionic-solid cohesive energy
- Born-Haber cycle: Hess's law applied to ionic-solid formation enthalpies
- NaCl 4-shell partial Madelung sum: -8√3/3 - 3 + 6√2 (sympy canonical)