Calculate lattice energy for ionic compounds using multiple methods
Kapustinskii: U = (1202 × v × |z⁺| × |z⁻|) / (r⁺ + r⁻)
Born-Landé: U = (1389 × A × |z⁺| × |z⁻|) / r₀ × (1 - 1/n)
Trends: Higher charges → higher U; Smaller radii → higher U
Applications: Predicts solubility, melting points, compound stability
Lattice energy is the energy required to completely separate one mole of an ionic solid into gaseous ions, or equivalently, the energy released when gaseous ions combine to form one mole of ionic solid. It's a crucial measure of the strength of ionic bonding and determines many properties of ionic compounds including melting point, hardness, and solubility.
Three main methods calculate lattice energy: the Kapustinskii equation (empirical, quick), the Born-Landé equation (theoretical, requires Madelung constant), and the Born-Haber cycle (experimental, uses thermodynamic data). Each provides insights into the energetics of ionic bonding.