Ian Tickle has just written a definitive answer to your first question, so I will just comment on questions 2 and 3.
SHELXD divides the occupancies by the occupancy of the first atom in the peaklist, so they should not be greater than 1.0. I was not able to find an example of an occupancy greater than 1.0 in a PDB file from SHELXD. Assuming that you are using the current version of SHELXD (2006/3) I would appreciate receiving more details. If you are using SHELXE for phasing only the RELATIVE occupancies are used anyway. Some useful statistics are printed out by SHELXC when it prepares the files for SHELXD and SHELXE. If you would like to display these nicely in graphical form you can use Thomas Schneider's hkl2map GUI to call SHELXC/D/E (strongly recommended anyway). George Prof. George M. Sheldrick FRS Dept. Structural Chemistry, University of Goettingen, Tammannstr. 4, D37077 Goettingen, Germany Tel. +49-551-39-3021 or -3068 Fax. +49-551-39-22582 On Wed, 22 Jul 2009, DebajyotiDutta wrote: > Dear Sir, > > I have very little knowledge about anomalous dispersion method. The thing is > that I have just started to deal with a case of SAD. I have consulted several > text books to acquire knowledge about it though I have some queries. CCP4BB, > I think is the best place to place my questions. > > 1.Is there any difference between Anomalous Dispersion and Anomalous > Scattering? > > 2.Sometimes I found that while searching for anomalous scatterer with SHELXD > which give the coordinates of the scatterer in PDB format with occupancy more > than 1. Why anomalous occupancy may be more than 1. > > 3.I found that there is one plot (FPH FP)/FP Vs Resolution indicate the > isomorphism but how can I get this plot does SHELX has any option to print it. > > > Thank you all for your time and reply to a beginners query in advance. > > Sincerely > Debajyoti Dutta >
