11453

# Radial Distribution Function for Hard Spheres

In statistical mechanics, the distribution of interparticle separations determines the radial distribution function [1].
This Demonstration shows the radial distribution function of a three-dimensional liquid composed of identical hard spheres of diameter , making use of the exact solution of the Percus–Yevick integral equation [2, 3]. You can vary the packing fraction of the liquid, that is, the fraction of the total volume occupied by the spheres themselves. For a packing fraction greater than about 0.49, the corresponding can be regarded as that of a metastable liquid since the true stable phase is a crystal.
The Demonstration also includes three functions directly related to the radial distribution function : the structure factor , the direct correlation function [6], and the bridge function [7].

### DETAILS

The exact solution of the Percus–Yevick integral equation for hard spheres was first obtained in [2] and [3]. The entirely analytic forms for the static structure factor were first presented in [4].
References
[2] M. S. Wertheim, "Exact Solution of the Percus–Yevick Integral Equation for Hard Spheres," Physical Review Letters, 10(8), 1963 pp. 321–323. doi:10.1103/PhysRevLett.10.321.
[3] E. Thiele, "Equation of State for Hard Spheres," The Journal of Chemical Physics, 39(2), 1963 pp. 474–479. doi:10.1063/1.1734272.
[5] Wikipedia. "Structure factor." (May 9, 2013) en.wikipedia.org/wiki/Structure_factor.
[6] Wikipedia. "Ornstein–Zernike equation." (April 20, 2013) en.wikipedia.org/wiki/Ornstein% E2 %80 %93 Zernike_equation.
[7] SklogWiki. "Bridge function." (November 7, 2012) www.sklogwiki.org/SklogWiki/index.php/Bridge_function.

### PERMANENT CITATION

 Share: Embed Interactive Demonstration New! Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details » Download Demonstration as CDF » Download Author Code »(preview ») Files require Wolfram CDF Player or Mathematica.

#### Related Topics

 RELATED RESOURCES
 The #1 tool for creating Demonstrations and anything technical. Explore anything with the first computational knowledge engine. The web's most extensive mathematics resource. An app for every course—right in the palm of your hand. Read our views on math,science, and technology. The format that makes Demonstrations (and any information) easy to share and interact with. Programs & resources for educators, schools & students. Join the initiative for modernizing math education. Walk through homework problems one step at a time, with hints to help along the way. Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet. Knowledge-based programming for everyone.