Hi folks, I am currently working on a project involving an unknown crystal sample. I have now identified the sample but I would like to quantify my findings by considering how well the structure I have determined fits other known structures. I have already ruled out fitting atomic positions to structures as this is very difficult unless the structures are very similar (same space group etc). I have instead opted to fitting a synthetic genetration of powder diffraction data for my crystal structure to synthetic generations from literature data. My question is really about how to check the goodness of this fit? As both data sets are synthetic I have no associated errors so I cannot use a traditional chi squared tests. Does anyone have a suggestion on how this may be performed or any other method I may consider for comparing crystal structure quantitatively? Cheers.