Dear all, I am trying to use EXAFS, along with other techniques, to attempt to find information about an unknown structure. It is an organic-inorganic hybrid material, EDX reveals Cu1-W1-O4 as the stoichiometry of the inorganic component, which we are most interested in structurally. We have not been able to solve the structure from XRD, although not for want of trying. I started off with CuWO4 as the model compound and constrained the fitting parameters: - take all 1st oxygen shells (x6 at slightly different distances) and give them all amp1, dr1*reff, enot and ss1 - take all 1st copper shells (x2) and give them both amp2, dr2*reff, enot and ss2 - take all 2nd oxygen shells (x6), amp3, dr3*reff, enot, ss3 - take all 1st tungsten shells (x6), amp4, dr4*reff, enot, ss4 This gave me 13 parameters with 14.8 independent points. (Other factors: fitted in kw=2&3, k-range 2-9, used Athena with default background subtraction parameters as the chi(k) from that seemed sensible. The data were collected at SSRL, beamline 11-2, in transmission.) I was happy with the final result (R-factor 0.014), but am just wondering if this is a sensible way to go about doing things - bearing in mind I am not sure of the structure in the first place. Any hints or advice would be much appreciated. I should have collected data at the tungsten edge as well, as it is not that much higher in energy from Cu, but this didn't occur to me until later. Regards, Bridget This electronic transmission and any documents accompanying this electronic transmission contain confidential information belonging to the sender. This information may be legally privileged. The information is intended only for the use of the individual or entity named above. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution or the taking of any action in reliance on or regarding the contents of this electronically transmitted information is strictly prohibited. This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.