Solution of the phase problem at non-atomic resolution by the phantom derivative method

Acta Crystallographica. Section A, Foundations and Advances
Carmelo Giacovazzo

Abstract

For a given unknown crystal structure (the target), n random structures, arbitrarily designed without any care for their chemical consistency and usually uncorrelated with the target, are sheltered in the same unit cell as the target structure and submitted to the same space-group symmetry. (These are called ancil structures.) The composite structures, whose electron densities are the sum of the target and of the ancil electron densities, are denoted derivatives. No observed diffraction amplitudes are available for them: in order to emphasize their unreal nature, the term phantom is added. The paper describes the theoretical basis by which the phantom derivative method may be used to phase the target structure. It may be guessed that 100-300 ancil structures may be sufficient for phasing a target structure, so that the phasing technique may be denoted as the multiple phantom derivative method. Ancil phases and amplitudes may be initially combined with observed target magnitudes to estimate amplitudes and phases of the corresponding phantom derivative. From them suitable algorithms allow one to obtain poor target phase estimates, which are often improved by combining the indications arising from each derivative. Probabilistic cr...Continue Reading

References

Sep 18, 1999·Acta Crystallographica. Section D, Biological Crystallography·K Cowtan
Oct 22, 2002·Acta Crystallographica. Section A, Foundations of Crystallography·Carmelo Giacovazzo, Dritan Siliqi
Jan 30, 2004·Acta Crystallographica. Section D, Biological Crystallography·Richard J MorrisGérard Bricogne
Apr 23, 2004·Acta Crystallographica. Section A, Foundations of Crystallography·Carmelo GiacovazzoAugusto Pifferi
Jul 1, 1993·Acta Crystallographica. Section D, Biological Crystallography·L S Refaat, M M Woolfson
Jan 1, 1996·Acta Crystallographica. Section D, Biological Crystallography·J P Abrahams, A G Leslie
Jul 1, 1997·Acta Crystallographica. Section D, Biological Crystallography·J P Abrahams
Apr 29, 2005·Acta Crystallographica. Section D, Biological Crystallography·Rocco CaliandroDritan Siliqi
Jul 26, 2005·Acta Crystallographica. Section D, Biological Crystallography·Rocco CaliandroDritan Siliqi
Jul 21, 2006·Acta Crystallographica. Section D, Biological Crystallography·J X YaoM M Woolfson
Sep 21, 2007·Acta Crystallographica. Section D, Biological Crystallography·Isabel UsónGeorge M Sheldrick
Apr 21, 2010·Acta Crystallographica. Section A, Foundations of Crystallography·Maria Cristina BurlaGiampiero Polidori
Apr 17, 2012·Acta Crystallographica. Section D, Biological Crystallography·Dayté RodríguezIsabel Usón
May 23, 2013·Acta Crystallographica. Section D, Biological Crystallography·Benedetta CarrozziniAnnamaria Mazzone
Jun 20, 2013·Acta Crystallographica. Section A, Foundations of Crystallography·B CarrozziniA Mazzone
Jul 10, 2014·Acta Crystallographica. Section D, Biological Crystallography·Rocco CaliandroAnnamaria Mazzone

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Citations

Sep 4, 2015·Acta Crystallographica. Section D, Biological Crystallography·Maria Cristina BurlaGiampiero Polidori
Apr 7, 2016·Acta Crystallographica. Section D, Structural Biology·Benedetta CarrozziniCarmelo Giacovazzo
Apr 28, 2017·Acta Crystallographica. Section A, Foundations and Advances·Maria Cristina BurlaGiampiero Polidori
Jan 8, 2020·Acta Crystallographica. Section D, Structural Biology·Maria Cristina BurlaGiampiero Polidori
Nov 3, 2017·Acta Crystallographica. Section D, Structural Biology·Maria Cristina BurlaGiampiero Polidori
Dec 24, 2018·Acta Crystallographica. Section A, Foundations and Advances·Carmelo Giacovazzo
Dec 7, 2021·Acta Crystallographica. Section D, Structural Biology·Giovanni Luca Cascarano, Carmelo Giacovazzo

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