Abstract
In direct methods quantities which are independent of the choice of origin are generally called structure invariants. Under certain conditions for some structure invariants numerical values can be estimated. Then they are called phase, relationships, or sometimes also invariants. However, it is sensible to make a distinction between all invariants and those, for which it is possible to estimate their phase sums. For direct methods the latter are of course the only important ones, because reliably estimated phase relationships are the basis of a reliable phasing method.
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Schenk, H. (1998). Invariants, Seminvariants and Phase Relationships. In: Fortier, S. (eds) Direct Methods for Solving Macromolecular Structures. NATO ASI Series, vol 507. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-9093-8_7
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DOI: https://doi.org/10.1007/978-94-015-9093-8_7
Publisher Name: Springer, Dordrecht
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