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  • 1
    Electronic Resource
    Electronic Resource
    La Fatigue des Métaux by R. Cazaud (1969)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 2 (1969), S. 234-234 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889869007060
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Technik-Wörterbuch Kristallografie. Englisch-Deutsch-Französisch-Russisch by K.-O. Backhaus (1973)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 6 (1973), S. 163-164 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889873008435
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Anomalous scattering edited by S. Ramaseshan and S. C. Abrahams (1976)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 32 (1976), S. 1037-1038 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739476002179
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  • 4
    Electronic Resource
    Electronic Resource
    On the application of phase relationships to complex structures. X. MAGLIN – a successor to MULTAN (1977)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 33 (1977), S. 219-225 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The MULTAN system has almost reached the limit of possible development. For complicated structures the starting set must be so large that even the largest computers cannot handle the number of phase permutations required. Another difficulty is that for some structures a correct set of phases is unstable under tangent-formula refinement. In the MAGLIN program now being developed initial sets of phases will be found for 30 or so reflexions by an application of magic integers to Karle-Hauptman determimants with the use of the Tsoucaris maximum-determinant rule. Further phases are then found by repeated application of magic integers. Phase refinement is carried out by a least-squares solution of a set of linear equations with each Σ2 relationship represented by one equation. A novel technique is described whereby a set of equations involving M reflexions may be solved for the phases of only m( 〈 M) of them. This leads to a considerable saving of time in running the MAGLIN process. For complicated structures it is expected that MAGLIN will not only be more effective than MULTAN but also considerably less time-consuming.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S056773947700045X
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  • 5
    Electronic Resource
    Electronic Resource
    On the application of phase relationships to complex structures. XVI. A random approach to structure determination (1978)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 34 (1978), S. 883-892 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: With triple-phase relationships treated as linear equations it is possible to refine a set of phases from given initial values. Phases so obtained are better than those found by refining to self-consistency with the tangent formula. An investigation of the radius of convergence of the least-squares refinement process showed that a substantially correct solution may often be found even starting with random phases. Systems containing up to 300 phases have been investigated and the results and their implications are discussed. It is concluded that the random approach can, at the very least, be used to obtain 70--100 phases as a good starting point for phase development. There is also the possibility of obtaining a sufficient number of phases directly to define a reasonably complex structure, especially with a computer augmented by an array processor. A problem which can arise with linear equations, as with the tangent formula, is that the phases obtained do not adequately define the enantiomorph and give an E map with a pseudo centre of symmetry. Two methods of overcoming this problem are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739478001837
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  • 6
    Electronic Resource
    Electronic Resource
    On the application of phase relationships to complex structures. XVII. When MULTAN fails (1979)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 35 (1979), S. 622-626 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Two new multisolution direct-methods procedures are described: MAGIC, which employs the magic-integer concept and YZARC which refines initially random sets of phases by a least-squares approach. Each procedure produces several sets of phases for a number of reflexions, usually in the range 35-100. These are then extended by the tangent formula but with the constraint that the basis phases are not allowed to change until the final cycle. It is shown that for difficult structures these methods, which deal simultaneously with many phase relationships, may have intrinsic advantages over the MUL TAN procedure. Examples of their use are given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739479001455
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  • 7
    Electronic Resource
    Electronic Resource
    The application of phase relationships to complex structures. VlI. Magic integers (1975)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 31 (1975), S. 53-56 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: With phases expressed in cycles so that 0 ≤ φ 〈 1 it is possible with a single symbol x, in the range 0 to 1, to represent several phases, say m, by φ = nix mod (1) where i runs from 1 to m and the integers, ni, are referred to as 'magic integers'. A starting set of phases may consist of some which fix the origin and enantiomorph, some known by Σ1 relationships for example and others given magic-integer representation in terms of x, y and z. Relationships between the starting-set phases then appear in the form Hx + Ky + Lz + b ∼ 0, and maxima of the function, ψ = \sum_{r} |E1rE2rE3r| cos {2π(Hrx + Kry + Lrz + b)} , lead to sets of possible values of the unknown phases in the starting set of reflexions. By means of the magic-integer process complex structures requiring very large starting sets may be tackled. Examples of the application of the method are given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739475000095
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  • 8
    Electronic Resource
    Electronic Resource
    How to use groups by J. W. Leech and D. J. Newman (1969)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 25 (1969), S. 1923-1923 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S056774086900495X
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  • 9
    Electronic Resource
    Electronic Resource
    Physics of simple liquids edited by H. N. V. Temperley, J. S. Rowlinson and G. S. Rushbrooke (1969)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 25 (1969), S. 1924-1924 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740869004961
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  • 10
    Electronic Resource
    Electronic Resource
    Crystals and their structures by A. P. Cracknell (1969)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 25 (1969), S. 2173-2174 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740869005401
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