On Wednesday 28 March 2007 08:18, Jim Pflugrath wrote: > Ethan, very nice web page. I like the discussion of required signal with > respect to one's diffraction experiment and counting statistics in the > results page. > > I will use this in my lecture tomorrow on SAD/MAD phasing. > > Do you mind putting Sulfur as one of the radio buttons?
I don't think that would make any sense. The radio buttons are for the theoretical f'/f" values at the absorption edge, but it is rather unlikely that anyone is actually collecting data at the S absorption edge. Instead you should use the accompanying tool http://skuld.bmsc.washington.edu/scatter/AS_form.html to determine the f' and f" terms from S at whatever wavelength you will be using, and type those into the form. > Also, do you mind putting 1.5418 A and 2.29 A as wavelengths among your > edge radio buttons? Are you still talking about the AS_signal page, or have you switched to talking about one of the other web pages on the site? The "edge buttons" on the AS_signal page fill in typical f' and f" for an arbitrary element at is own K or L edge. Selecting a fixed wavelength doesn't make sense in this context. I'd have to add a separate section in the form that takes both an element and a wavelength as input, and generates theoretical (as opposed to experimental) f' and f" values. That is certainly possible, but won't be there in time for your lecture tomorrow :-) Ethan > Thanks! Jim > > On Wed, 28 Mar 2007, Ethan A Merritt wrote: > > > On Wednesday 28 March 2007 07:35, Joyce, Gordon M.(NIH/NIAID) [F] wrote: > >> > >> I would like to know the phasing power of different heavy atoms ie how > >> many seleniums per 10 kDa would be good enough to solve the structure. I > >> wonder is there a good website or some useful publications that people > >> know of, that would give this information, not just for Selenium but for > >> other atoms as well. > > > > http://skuld.bmsc.washington.edu/scatter/AS_signal.html > > > > > > -- > > Ethan A Merritt > > Biomolecular Structure Center > > University of Washington, Seattle 98195-7742 > > > -- Ethan A Merritt Courier Deliveries: 1959 NE Pacific Dept of Biochemistry Health Sciences Building University of Washington - Seattle WA 98195-7742