[cctbxbb] Best way to compare two structures using cctbx?

[Luc Bourhis]

On 12 Mar 2013, at 16:56, Jan Marten Simons wrote:

> Right now I wonder where one would put a cut-off on rms with respect to
> a) the structures disagree substantially
> b) the structures have the same scatterers but at completely different 
> positions relative to each other or the symmetry elements
> c) the structures are quite similar (e.g. you only have to move a single 
> scatterer a little)
> d) the structures are identical within the tolerance limit (apart from origin 
> shifts).
> 
> Is there a paper I could read for reference and can you give some rule of 
> thumb rms intervals for the cases mentioned above?

I don't know of any paper I am afraid. I think that you need to look at the distribution of the distances between the members of each matched pair. Then (c) would be characterised by one of those distance being much bigger than all the others whereas (d) would have a flat distribution near zero. I am not sure I understand what you mean by (b) and (a) on the other hand.

Best wishes,

Luc