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1.http://www.phy.cmich.edu/people/petkov/isaacs/phys/rdfs.html
2.http://www.iams.sinica.edu.tw/lab/jlli/thesis_andy/node14.html
3.http://en.wikipedia.org/wiki/Radial_distribution_function
4.http://imagejdocu.tudor.lu/doku.php?id=macro:radial_distribution_function
5.http://muchong.com/bbs/viewthread.php?tid=2395138
6.http://www.materialssimulation.com/node/185
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The Radial Distribution Function, R.D.F. , g(r), also called pair distribution function or pair correlation function, is an important structural characteristic, therefore computed by I.S.A.A.C.S..

Figure 1: Space discretization for the evaluation of the radial distribution function.
Considering a homogeneous distribution of the atoms/molecules in space, the g(r) represents the probability to find an atom in a shell dr at the distance r of another atom chosen as a reference point [Fig. 1].
By dividing the physical space/model volume into shells dr [Fig. 1] it is possible to compute the number of atoms dn(r) at a distance between r and r + dr from a given atom:
 = (N/V)*g(r) 4¦Ðr^2dr (1))
where N represents the total number of atoms, V the model volume and where g(r) is the radial distribution function.

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