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Dear Jakob,
the inverse resolution of a reflection equals the length of the vector
h*astar + k*bstar + l*cstar.
does this explain your 'PS'?
Best,
Tim
On Friday, April 15, 2016 04:08:56 PM Keller, Jacob wrote:
> Dear Crystallographers,
>
> In detwinning a dataset, I noticed that correction of the intensity
> distributions works dramatically better for the acentric versus centric
> (see attached plots). In this case it is P3212 and the twin operator is
> (-h,-k,l). Can anyone suggest why this might be the case? Should the
> algorithm be different for centrics than for acentrics (I can't see
> why...)?
>
> All the best,
>
> Jacob Keller
>
> PS: btw, I came across an interesting phenomenon in this spacegroup which
> experienced crystallographers no doubt will be aware of, but just felt it
> amusing enough to share. When there is a non-orthogonal axis, HKL's of
> seemingly-different resolution can be the same resolution. For example, in
> this spacegroup, the two reflections (3,2,4) and (-5,3,4) are equivalent
> reflections and are of the exact same resolution. This is because when one
> "walks down" the H axis in reciprocal space 3 units and up 2 units in K,
> the walk up K takes you *farther* from the origin due to the 60 deg angle
> between K and H. Conversely, when one walks down H -5 units, then up 3
> units, the 3 units in K bring you *closer* to the origin, again due to the
> tilt of K with respect to H. I thought this might be interesting to
> somebody out there.
>
>
> *******************************************
> Jacob Pearson Keller, PhD
> Looger Lab/HHMI Janelia Research Campus
> 19700 Helix Dr, Ashburn, VA 20147
> email: [log in to unmask]
> *******************************************
- --
- --
Paul Scherrer Institut
Tim Gruene
- - persoenlich -
OFLC/102
CH-5232 Villigen PSI
phone: +41 (0)56 310 5297
GPG Key ID = A46BEE1A
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