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Absent reflections lattice type

Refers to the Miller indices (Shkl) values) that are absent from the diffraction pattern. For instance, a body-centered cubic lattice with no other screw axes and glide planes will have a nonzero intensity for all reflections where the sum oi Qi + k + 1) yields an odd number, such as (100), (111), etc. other reflections from planes in which the sum of their Miller indices are even, such as (110), (200), (211), etc. will be present in the diffraction pattern. As these values indicate, there are three types of systematic absences three-dimensional absences (true for all hkl) resulting from pure translations (cell centering), two-dimensional absences from glide planes, and one-dimensional absences from screw axes.[261... [Pg.378]

The pattern we have just indexed is for a primitive lattice where all reflections are observed. In the other types of cubic lattice, certain types of reflection are absent and these are called systematic absences. [Pg.61]

What type of cubic lattice would have a diffraction pattern where the 110 reflection would be observed but the 234 would be absent Give reasons for your answer. [Pg.79]


See other pages where Absent reflections lattice type is mentioned: [Pg.240]    [Pg.26]    [Pg.140]    [Pg.280]    [Pg.441]    [Pg.237]    [Pg.238]    [Pg.268]    [Pg.152]    [Pg.249]    [Pg.1107]    [Pg.211]    [Pg.138]    [Pg.1106]    [Pg.121]   
See also in sourсe #XX -- [ Pg.232 ]




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Absent reflections

Lattice types

Reflective type

Reflectivity types

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