The structure factor, , for a monatomic system is defined by:
where is the scattering wave-vector modulus
The structure factor is basically a Fourier transform of the pair distribution function ,
At zero wavenumber, i.e. ,
from which one can calculate the isothermal compressibility.
To calculate it in computer simulations one typically uses:
- <math> S(k) = \frac{1}{N} \sum^{N}_{i,j=1} \left<\exp(-i(r_i-r_j))\right>
References
- A. Filipponi, "The radial distribution function probed by X-ray absorption spectroscopy", J. Phys.: Condens. Matter, 6 pp. 8415-8427 (1994)