Lattice energies and polarizability volumes of lanthanide monoaluminates

Lattice energies ΔLHΘ of the entire series of lanthanide aluminum perovskites LnAlO3, Ln=Ce–Lu, have been determined for the first time by means of the Born–Haber cycle. The results have been compared for LnAlO3 obtained by other methods, with cubic lanthanide sesquioxides (C-Ln2O3) and lanthanide aluminum garnets (Ln3Al5O12). Polarizability volumes αI of LnAlO3 have been estimated by the Clausius–Mossotti equation. It has been found that the partial derivative (∂ΔLHΘ/∂αI)T corresponds by magnitude to an upper limit of elastic moduli of the same crystals.