Dear All,

            I am experiencing problem during my fit for Fe(OTf)2 anhydrous. The problem is as follows.

I collected the data and used a model to fit. The fitting values and other technical information is as below. The basic problem is Fe(OTf)2 in anhydrous condition is probably not cyrstalline because of which there are no crystal data available. Although .cif file is available for hexahydrate and tetra acetonitrile. But obviously it is not directly useful as I am looking for Fe(OTf)2 only. I used hexahydrate for fitting, and the fit information is given. Is this fit acceptable?

Now two questions

1) Why do I not see any scattering or peak for Fe-S. I expected S to be a strong scatterer and would  show a peak. Under given circumstances it looks like Fe is all surrounded by water and no triflate is present near Fe at all. Is this assumption even make sense (when the bottle said anhydrous) The bottle was not kept under inert condition (and its my fault), but does it mean Fe(OTf)2 is so hygroscopic and that it can actually form such hexahydrate to the full extent?

OR there is some inherent problem with my fitting and collection itself. I used RBKG=1.0

2) Is anybody working on Fe(OTf)2 and had such or any other problem indicating that Fe(OTf)2 by itself is a bad choice of precursor because of its reactivity. Also any comments on purification method etc. does anybody know if crystal structure is available for Fe(OTf)2 anhydrous? I could not find it on the quick search or on CCDC. Any other site where I can get crystal data and .cif information?

Thank you very much for all the help, I hope the question is asked appropriately and all the other information is provided, however, if anybody needs any other information please let me know.

Thank you in an anticipation

Best

Pushkar

Independent points          : 16.1250000

Number of variables         : 4

Chi-square                  : 7324.9401796

Reduced chi-square          : 604.1187777                                       

R-factor                    : 0.0195782                                         

Measurement uncertainty (k) : 0.0001264

Measurement uncertainty (R) : 0.0004142

Number of data sets         : 1

guess parameters:                                                               

  SO                 =   1.06525455    # +/-   0.05504541     [1.00000]

  delE               =  -2.32587026    # +/-   0.59606221     [-2.77870]

  delR               =   0.00911122    # +/-   0.00503027     [-0.02322]

  ss                 =   0.00706809    # +/-   0.00071967     [0.00300]

Correlations between variables:                                                 

                delr & dele               -->  0.9154

                  ss & so                 -->  0.9023

All other correlations below 0.4

 name        N       S02     sigma^2   e0     delr     Reff     R

=========================================================================

 O1.1      6.000   1.065   0.00707  -2.326  0.00911  2.09150  2.10061

--

Best Regards,
Pushkar Shejwalkar.
Post-doctoral -Researcher,JSPS Fellow

Hokkaido University,

Sapporo,

Japan

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