On Tuesday 05 December 2006 13:02, Scott Calvin wrote:
P.S. Just as I finished writing this, Matthew Marcus' post came through. I do have Pt foil data in transmission that I can dig up for you, if you'd like. Maybe I'll send it to Matt to put in the database; it's pretty good quality, as I recall (good data out to 20 inverse angstroms or so).
A few years ago, when I was commissioning X11b at NSLS, I prepared a some reports on how things were progressing. This one: http://cars9.uchicago.edu/~ravel/misc/X11b/update_sep02.html includes a link to an athena project file containing my measurements there on several foils and filters that we had lying around X11, including a Pt foil. It comes with all the caveats that the others have already discussed. I agree with what others have said -- Juan would be best served by remeasuring the Pt foil in transmission. That's not, however, the most immediately useful advice. Juan has a problem that he needs to solve *now*. It is quite possible that he will not be able to go to a synchrotron for quite some time. Suggesting that he is stuck until he returns to the synchrotron just isn't especially helpful. What I would recommend, Juan, to get you over this road block is to compare your measured data to the data from my project file or to someone else's data (or both!). Work on the self-absorption correction until your fluorescence data most closely resembles the data you are comparing to. Then proceed with your data analysis using the many excellent suggestions you have received so far. The *next* time you go to measure data, think really hard about how best to measure each of your samples and standards. Try to figure out how to measure the best possible data from each sample. Different samples require different experimental protocols. The goal is, of course, to obtain consistently excellent data, so you will need to be resourceful and do what each sample requires. As helpful as it is to have a slew of "experts" (y'know, disreputable sorts like me) telling you what you need to do, you must remember that your education is a process. If you learn from the mistakes you made last time and improve upon them next time, then you are proceeding in the correct direction. B -- Bruce Ravel ---------------------------------------------- bravel@anl.gov Molecular Environmental Science Group, Building 203, Room E-165 MRCAT, Sector 10, Advanced Photon Source, Building 433, Room B007 Argonne National Laboratory phone and voice mail: (1) 630 252 5033 Argonne IL 60439, USA fax: (1) 630 252 9793 My homepage: http://cars9.uchicago.edu/~ravel EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/