Vegard's law

Vegard's law is a principle in solid-state physics that describes the relationship between the composition of a solid solution and its lattice parameters. Specifically, it states that the lattice constant (or parameter) of a solid solution is a linear function of the composition of its constituents. In simpler terms, when two or more different materials are mixed to form an alloy or a solid solution, the resulting lattice structure will have a lattice parameter that can be predicted based on the proportions of the constituent materials.