Short-Range Order SRO and MRO

Correlations in the relative position of atoms determine the SRO and MRO. The spatial distribution of atoms is described by N-particle (N = 1,2. ) distribution functions. The single-particle distribution functions represent the probability densities of the existence of atoms with different LO X) is the 

A two-particle distribution function can be represented as a product of a single-particle distribution function n (A 1) by the density of the conditional probability /, (3f1( X2), meaning that at point X2 there is an atom with a / -type LO if at point Xt there is an atom with an a-type LO 

For a homogeneous random network, nafi depends only on X2 — Xlt and if the network is isotropic, then it depends only on X2 — X2. In this case, we have 

In the absence of a long-range order, the two-particle distribution functions and RDF possess evident asymptotic properties 

The partial RDFs are related to the functions of radial density distribution around the atom. Describing the density fluctuations around the atom with an a-type local order by the sum 

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