-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Dear James,
my guess is that xprep removes ( 0 0 0) for a better contrast, but I don't know for sure - George is going to tell you, I guess, because he will know ;-) The reason I answer is rather a comment: I would not call the tutorial you refer to a 'manual' (I don't think a manual for xprep exists). It's really a tutorial for students to learn small molecule (singe crystal) crystallography and as far as I remember it was created by Eftichia Alexopoulos & Fabio Dall'Antonia (main url is http://shelx.uni-ac.gwdg.de/tutorial/english/) and further improved by other PhD students of George's - they did a really good job worth working through, but since it is a tutorial with a certain objective rather than a manual there is no reference to ALL capabilities of xprep. Best, Tim On 04/20/2013 03:42 AM, James Stroud wrote: > Hello All, > > I calculated structure factors from a pdb with sfall and then used > those to generate a simulated powder diffraction pattern with > xprep. To compare, I also plotted the intensities (F x F*) straight > from the mtz file. Attached are the two patterns as png files > (sfall only: "mtz.png"; sfall→xprep: "xprep.png"). > > Does anyone know what xprep is doing to the low resolution data (> > ~20 Å)? It seems to be clipped. The xprep manual[1] says nothing > about simulated powder diffraction. The patterns < ~20 Å are > more-or-less comparable (although you can't tell from the > pictures). > > James > > > [1] http://shelx.uni-ac.gwdg.de/tutorial/english/xprep.htm > > > > - -- Dr Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iD8DBQFRdSYwUxlJ7aRr7hoRAh0kAJ9zkQ/xRn0GvLzE83FdYHxsTENPYACg3XoY K7iBOAs903lL32PfSzioWPI= =SlGZ -----END PGP SIGNATURE-----