Hi Jason: On Tue, 11 Jun 2013, Jason F. Alvino wrote:
Hi Matt,
As I pointed out before, in the attached zipfile, there is a file called "AuNP_anatase_Au.D" which has the data in two columns of energy vs mu, comma separated underneath the "EV RAW" header.
It also already has all the bad channels removed from the averaged data.
Just doing a quick fit of your data with k 2-15 and R 1-6 and a bulk gold model (all paths up to 8 A), gives an excellent fit with 5 parameters (R ~ 2%). It basically looks like bulk Gold at low temperatures with an amplitude reduction factor of 0.77 which is not too small. You are correct that the sigma squared values are samll but that is to be expected at 12K. I used an isotropic expansion/contraction parameter which fits to -0.010, again consistent with thermal expansion at low temperatures. It looks like you indeed have agglomeration because this data does not seem to be from nanoparticles of gold. Cheers, Carlo -- Carlo U. Segre -- Duchossois Leadership Professor of Physics Director, Center for Synchrotron Radiation Research and Instrumentation Illinois Institute of Technology Voice: 312.567.3498 Fax: 312.567.3494 segre@iit.edu http://phys.iit.edu/~segre segre@debian.org