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Novel phasing method using the origin-free modulus sum function expressed in terms of the absolute electron density.

ABSTRACT: The origin-free modulus sum function S_M refines the set Φ of phases of the structure factors by maximizing the coincidence between the experimental origin-free modulus function and the calculated one in terms of the ρ(Φ)² density function [Rius, J. (1993). Acta Cryst. A49, 406-409]. Maximization is normally achieved through the recursive application of a Fourier-based algorithm. The purpose of the present study is: (i) to show that ρ(Φ)² can be replaced by |ρ(Φ)| in S_M; (ii) to illustrate the viability of the corresponding phasing algorithm with experimental data.

SUBMITTER: Rius J

PROVIDER: S-EPMC7331883 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Novel phasing method using the origin-free modulus sum function expressed in terms of the absolute electron density.

Rius Jordi J

Acta crystallographica. Section A, Foundations and advances 20200601 Pt 4

The origin-free modulus sum function SM refines the set Φ of phases of the structure factors by maximizing the coincidence between the experimental origin-free modulus function and the calculated one in terms of the ρ(Φ)2 density function [Rius, J. (1993). Acta Cryst. A49, 406-409]. Maximization is normally achieved through the recursive application of a Fourier-based algorithm. The purpose of the present study is: (i) to show that ρ(Φ)2 can be replaced by |ρ(Φ)| ...[more]

PMID: 32608364

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