Calculation of the effective ionic radii of Al1+ and Al2+, the standard enthalpies of formation of the crystalline oxides Al2O, AlO, and Al3O4, and the enthalpies of their crystal lattices

The sizes of particles (ions and their associations) that participate in processes related to heat and mass transfer and electrotransport in condensed matter, as well as the interaction of the particles, are of importance. The effective radii of the Al¹⁺ and Al²⁺ ions are calculated in accordance with models proposed earlier. The standard enthalpies of formation of the Al₂O, AlO, and Al₃O₄ oxides and their crystal lattices are determined using these effective ionic radii. The coincidence of the parameters that have been calculated using independent models and initial data for different oxides indicates that these models are reliable and can be used for predictions. The calculated data bring the crystal structure parameters and the thermochemical constants of the oxides into agreement. Original Russian Text ? A.G. Ryabukhin, V.E. Roshin, A.V. Roshin, 2007, published in Metally, 2007, No. 2, pp. 11–18.