Reciprocal-Space Approach for Atomic Interactions and Configuration Correlations in Inhomogeneous Systems

Reciprocal space configurational thermodynamics of disordered systems [1,2] deals with cooperative concentration modes that take into account statistical coupling, which is essential for studies of highly inhomogeneous (liquid, amorphous) states. The main parameter of this theory is a Fourier component of the inter-particle potential function. The form of this function determines the structural and thermodynamic behavior of a system. Therefore, the right choice of the potential in statistical-thermodynamic modeling is of crucial importance. Coherent scattering data enables the extraction of parameters to construct an interaction potential, which is used to calculate two-body and, especially, many-body correlation functions. By this token, orientational pair-pair correlations are of particular interest in the present study since they describe bond-angle distributions as well as mid-range correlations.