Two conceptualizations of the partial structures and of the order parameters in the ternary alloy and relationships between them

Abstract Based on our two previous works (B. Grosdidier 2018 and 2019) and on rigorous calculations, we investigate the structure and the order in the ternary alloy. We show that the order may be described by two conceptualizations. The first describes the order of one species i with respect to the subsystem j and k. The second describes the order of one species i with respect to species j under the influence of species k. We calculate all structural quantities and the relationships between them. We develop the formula of the order parameters and we consider its application to seven “toy models”. We observe that the sequence in the changes of order is very important, which leads us to improve the definition of the order parameters. We successfully apply our formalism to the liquid alloy Al0.65Ni0.15Si0.20 to verify the consistency of these two conceptualizations and the quality of our development.