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Optical resolution

  • Page ID
    17425
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    By analogy with optical observations, e.g. in astronomy, the term optical resolution in structure determination,\(d_{opt}\), is used to describe the expected minimum distance between two resolved peaks in an electron-density map.

    \[d_{opt}=[2(\sigma^2_{Patt}+\sigma^2_{sph})]^{\frac{1}{2}} \nonumber \]

    where σPatt is the standard deviation of the Gaussian function fitted to the Patterson origin peak, σsph is the standard deviation of the Gaussian function fitted to the origin peak of the spherical interference function, representing the Fourier transform of a sphere with radius 1 / dmin, and dmin is the nominal resolution.


    Optical resolution is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Online Dictionary of Crystallography.