A consistent formalism for partial structure functions

The structure of an amorphous binary system can be described by three partial structure functions and their Fourier transforms relating to the atomic interactions. The experimental total function is the weighted sum of the partials. Two different formalisms, the Faber-Ziman and Ashcroft-Langreth, are generally applied for expressing the weights. This paper suggests a third formalism, created by taking into consideration the physically established features of both of the other formalisms. It is free from the difficulties that may arise when these formalisms are used.