>I tell people it is when your resolution is less than the bond length that >connects the two atoms.
I thought this was sort of a pitfall, since the Bragg spacings don't necessarily map on to conventional resolution. But it would fit the 1.5 Ang estimate. Also, resolution would depend a lot on phase accuracy/precision, no? JPK On Thu, Jan 11, 2018 at 1:59 PM, Thomas Edwards <t.a.edwa...@leeds.ac.uk> wrote: > Dear Jacob, > > Ah... this old chestnut! > > Current EM people say that they are at atomic resolution because they > are building atomic models (naive??). > > I have been criticised in the past for using the term with say 2.2A > diffraction data. By co-authors and reviewers alike. When I was young > and naive. > > My (current) definition would be yours - visible with data. > I think 1.5A is about right for X-ray. Maybe higher res? > > I’m sure there are lots of rigorous ways to think. I probably haven’t > taken that route. However, I think it is a semantic problem that might > benefit from some disambiguation rather than rigour. > > It depends why you are asking the question... > > Sorry..! > > Ed is: Out and about... > Sent from iPhone6sPlus. > > On 11 Jan 2018, at 19:31, Keller, Jacob <kell...@janelia.hhmi.org> wrote: > > Dear Crystallographers, > > > > Has there been a consensus as to what is meant by “atomic resolution?” > Seems like the term is taken by various practitioners to mean different > things. > > > > A related question: at what resolution are atoms “visible” using only > the data? I have an empirical feeling that this would be around 1.5 > Ang Bragg spacings, but on the other hand, one can contour up most > maps and see individual atom peaks. I would be interested to hear a > more rigorous way to think about this. > > > > All the best, > > > > Jacob Keller > > > > +++++++++++++++++++++++++++++++++++++++++++++++++ > > Jacob Pearson Keller > > Research Scientist / Looger Lab > > HHMI Janelia Research Campus > > 19700 Helix Dr, Ashburn, VA 20147 > > (571)209-4000 x3159 > > +++++++++++++++++++++++++++++++++++++++++++++++++ > > > > The content of this email is confidential and intended for the > recipient specified in message only. It is strictly forbidden to share > any part of this message with any third party, without a written consent of > the sender. > If you received this message by mistake, please reply to this message > and follow with its deletion, so that we can ensure such a mistake > does not occur in the future. > >
