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In condensed matter physics and crystallography, the static structure factor (or structure factor for short) is a mathematical description of how a material scatters incident radiation. The structure factor is a critical tool in the interpretation of scattering patterns ( interference patterns ) obtained in X-ray , electron and neutron ...
In condensed matter physics, the dynamic structure factor (or dynamical structure factor) is a mathematical function that contains information about inter-particle correlations and their time evolution. It is a generalization of the structure factor that considers correlations in both space and time.
After crystallographic image processing, [21] structure factor phase angles are far more reliable than structure factor amplitudes. Further discernment of candidate structures is then mainly based on structure factor phase angles and, to a lesser extent, structure factor amplitudes (so-called 'structure factor fingerprinting'). [22] [23]
Now we see the overall structure factor may be represented as a weighted sum of structure factors () corresponding to each atom. Set the displacement between the location in space for which we would like to know the scattering density and the reference position for the nucleus equal to a new variable t → = x → − x → k 0 {\displaystyle ...
The pair correlation function is related via Fourier transform to the static structure factor, which can be determined experimentally using X-ray diffraction or neutron diffraction. The OZ equation relates the pair correlation function to the direct correlation function. The direct correlation function is only used in connection with the OZ ...
The structure factor is a complex number containing information relating to both the amplitude and phase of a wave. In order to obtain an interpretable electron density map , both amplitude and phase must be known (an electron density map allows a crystallographer to build a starting model of the molecule).
In crystallography, the R-factor (sometimes called residual factor or reliability factor or the R-value or R Work) is a measure of the disagreement between the crystallographic model and the experimental X-ray diffraction data - lower the R value lower is the disagreement or better is the agreement.
One can determine () indirectly (via its relation with the structure factor ()) using neutron scattering or x-ray scattering data. The technique can be used at very short length scales (down to the atomic level [ 10 ] ) but involves significant space and time averaging (over the sample size and the acquisition time, respectively).