Talk:Octahedral cluster

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Image:Edgecappedoctahedralcluster.gif

  • Smokefoot, exactly what is wrong with this image?
My recollection is that 12 halides bridge edges in the Nb6/Ta6 series, with six terminal ligands, not a mixture of both mu-3 and mu-2 halides. The Inorg Syn ref gives an example of the Ta6Cl18 cmpd. I'll check again because I dont have sources with me now. Cheers,--Smokefoot 19:34, 30 June 2007 (UTC)
  • Dear Smokefoot, this is unacceptable: I know the structure is right because I reproduced it from reference 1 given in the text. You on the other hand think that the structure is wrong without providing references. And what happened to simply requesting the original author to have the images redrawn? In the past have done many many redrawings based on suggestions from others. I am happy to do that but instead you simply delete stuff. I suggest you put the image back in until you can prove you case V8rik 20:17, 30 June 2007 (UTC)
Dear V8rik: I was doing what I thought that I should, although not in a particularly communicative way (I should have known that you made the drawings since you like color in ChemDraw). These M6Xn things are tricky both in executing the drawing and in perceiving the connectivities. We could contact Ben who does these things with higher level graphics. If you want to edit the ChemDraw: (i) move the eight red face-cappers to be coplanar with the two other M4 planes (the four black anions are in correct positions), (ii) remove one M---X bond for each of these red anions (they are mu-2), and (iii) for consistency, change them to black. Keep up your incredible efforts, and again sorry to not be more communicative. Cheers,--Smokefoot 21:25, 30 June 2007 (UTC)

[edit] Nb6F15

Knoll, R.; Sokolovski, J.; BenHaim, Y.; Shames, A. I.; Goren, S. D.; Shaked, H.; Thepot, J. Y.; Perrin, C. and Cordier, S., "Magnetic resonance and structural study of the cluster fluoride Nb6F15", Physica B: Condensed Matter (Amsterdam, Netherlands), 2006, 381, 47-52. Abstract: "In this work, we report updated structural data, obtained by single-crystal x-ray diffraction, on the binary fluoride Nb6F15 as well as measurements of 19F NMR over the temp. range 100-300 K, and EMR measurements over the temp. range 4-300 K. Nb6F15 is built up from Nb6Fi12 Fa6 octahedral cluster units sharing all apical fluorine ligands to form linear Nb-Fa-Nb interunit bridges (Fi: inner fluorine located in edge-bridging position, Fa: apical fluorine located in terminal position). The 19F NMR results showed two resonance lines. One line corresponds to the inner fluorine Fi in the (Nb6F12)-3 cluster core. The second 19F NMR line corresponds to the apical Fa. The shift of the NMR signal from Fi depends on the temp. and exhibits a Curie type behavior, while the position of the NMR signal from Fa is temp. independent. EMR measurements show a single Lorentzian line. The temp. dependence of the inverse of the intensity of the EMR line shows a Curie-Weiss behavior and an onset to an antiferromagnetic (AF) order at 5 K." --Smokefoot 23:22, 2 July 2007 (UTC)

  • I have been able to check my reference and I can now report your analysis is correct. I have made the required changes. Thanks for pointing out the mistake made. V8rik 19:08, 3 July 2007 (UTC)