[Ifeffit] CN and bond distances in Artemis

[Bruce Ravel]

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 at anl.gov

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