Variation of interatomic interaction and lattice parameters in alloys during ordering

A method is suggested for calculating the change in interatomic interaction and in lattice parameters of alloys due to the ordering process. The method is based on solving the equation of state of alloys (deltaE/deltaΛ)sub(s)=-p, where E is the energy of the alloy being ordered, the energy value being determined with the aid of pseudopotential theory. The energy input related to ordering is investigated on the basis of the statistic-thermodynamic theory of ordering. Numerical calculations were made for the Ba-Cd and Mg-Cd system ordered structures, and their results agreed well with the experimental data