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| To calculate <math>S(k)</math> in computer simulations one typically uses: | | To calculate <math>S(k)</math> in computer simulations one typically uses: |
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| :<math>S(k) = \frac{1}{N} \sum^{N}_{i,j=1} \left<\exp(-i\mathbf{k}(\mathbf{r}_i-\mathbf{r}_j))\right> </math> | | :<math>S(k) = \frac{1}{N} \sum^{N}_{i,j=1} <\exp(-i\mathbf{k}(\mathbf{r}_i-\mathbf{r}_j))> </math> |
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| :<math>S(k) = \frac{1}{N} \sum^{N}_{i,j=1} \left< \exp(-i(r_i-r_j)) \right></math>
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Revision as of 17:30, 15 September 2011
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 in computer simulations one typically uses:
References
- A. Filipponi, "The radial distribution function probed by X-ray absorption spectroscopy", J. Phys.: Condens. Matter, 6 pp. 8415-8427 (1994)