Pair distribution function

The pair distribution function describes the distribution of distances between pairs of particles contained within a given volume. Mathematically, if a and b are two particles, the pair distribution function of b with respect to a, denoted by g a b ( r → ) {\displaystyle g_{ab}({\vec {r}})} is the probability of finding the particle b at distance r → {\displaystyle {\vec {r}}} from a, with a taken as the origin of coordinates.

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