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Twinning (consequences of)

  • Page ID
    19622
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    By effect of a twinning operation, both the direct and reciprocal lattice of the individuals forming a twin are overlapped. Overlapping (restoration) of nodes belonging to different individuals can be: (i) exact and total (twinning by merohedry); (ii) exact but partial (i.e. only a fraction of the nodes of an individual lattice is restored; twinning by reticular merohedry); (iii) total but approximate (twinning by pseudomerohedry), approximate and partial (twinning by reticular pseudomerohedry).

    • twin index

    The reciprocal n of the fraction 1/n of (quasi)restored nodes is called twin index

    • twin lattice

    The lattice that is formed by the (quasi)restored nodes is the twin lattice. It corresponds to the crystal lattice in twins by (pseudo)merohedry and to a sublattice of the crystal (individual) in twins by reticular (pseudo)merohedry.

    • twin obliquity

    The twin obliquity is a measure of the distortion of a (sub)lattice in twins by (reticular) pseudomerohedry.


    Twinning (consequences of) is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Online Dictionary of Crystallography.