LatticeEnergien

Lattice energy is the energy released when gaseous ions attract to form a solid ionic lattice. It can also be defined as the energy required to completely separate a solid ionic compound into its gaseous ions. Lattice energy is a measure of the strength of the ionic bond in the crystal and is influenced by the charges of the ions and their sizes, as well as the arrangement of ions in the lattice.

In general, higher charges and smaller radii yield larger lattice energies; for example, the lattice energy is much larger for MgO than for NaCl, reflecting stronger ionic interactions. The Madelung constant and lattice geometry account for differences among crystal structures; simple estimates use charge magnitudes and interionic distances in a Coulombic model, often in conjunction with the Madelung constant.

Measuring lattice energy directly is difficult; it is usually estimated from thermochemical data using the Born-Haber cycle, which relates lattice energy to the enthalpy of formation, sublimation energies, ionization energies, and electron affinities. More detailed calculations employ the Born-Lande model or other lattice energy equations. Limitations include neglect of covalent character and polarization effects in real materials, which can cause deviations from idealized values.