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New Trends in Determination of Crystal Structure

  • Jindřich Hašek

Abstract

Direct methods1 have become dominant in the determination of well-ordered crystal structures. They are based on an estimate of seminvariant values from distributions of seminvariants.* From any seminvariant one can thus form an equation
$$ {{f}_{i}}({{\varphi }_{1}}, \ldots ,{{\varphi }_{n}}) = {{\Phi }_{i}}\pm {{d}_{i}}, $$
(1)
where Фi is the expected value of seminvariant and di. is an unknown error related statistically to the distribution width. (When fi is a periodic function, the right side has to be taken modulo.)

Keywords

Phase Relation Level Structure Phase Error Acta Cryst Diffraction Vector 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Jindřich Hašek
    • 1
  1. 1.Institute of Macromoleculaar ChemistryCzechoslovak Academy of SciencesPraha 6Czechoslovakia

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