Local squaring functions for non-spherical templates.

Jeffrey Roach; Charles Carter

doi:10.1107/s0108767303007153

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Local squaring functions for non-spherical templates.

Jeffrey Roach·Charles Carter

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Abstract

The local squaring functions representing the likelihood that a particular atom type occupies a particular location in the unit cell are generalized so that the likelihood that a multiatom fragment occurs at a given position can be modeled at less than atomic resolution. The orientation space of the fragment is parameterized according to the special unitary 2-group in order to facilitate both interpretation and interpolation. The representation theory of this group is related to the harmonic analysis for functions of rotation. As an example of computer-aided model construction, local squaring functions for several protein backbone fragments are applied to a 2.0 A model electron density. The resulting functions are sufficient to reconstruct the atomic structure from the probable template placements.

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Conotoxins Crystallography, X-Ray Fourier Analysis Likelihood Functions Mathematical Computing Models, Chemical Models, Molecular Static Electricity Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Jeffrey Roach, Charles Carter. 2003-04-25. Local squaring functions for non-spherical templates.. https://doi.org/10.1107/s0108767303007153

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