Fe4 l

Finally, the study of a range of star-shaped Fe4 clusters has actually allowed devising a magnetostructural correlation for second order anisotropy terms [Fe4(L)2 (dpm)g] (Hdpm = 2,2,6,6-tetramethylheptane-3,5-dione H3L = R 0CH2C(CH20H)3 with R = alkyl and related moieties) [58, 59]. A clear... 

For high concentrations (pressure) B, fe3CB/fe4 l fe2CB/fe i l and the initial selectivity will be dependent on the concentration (pressure) of B, thus influencing the selectivity ... 

Zboril R, Machala L, Mashlan M, Sharma V (2004) Iron(III) oxide nanoparticles in the thermally induced oxidative decomposition of prussian blue, Fe4[Fe(CN)6]3. Cryst Growth Design 4(6) 1317-1325... 

Figure 1 Cyclic voltammogram recorded at a platinum electrode in a MeCN solution of f Fe4( /JLrS)4( l-C5H5)4]...

With 13 carbonyls, the metal atoms can adopt the usual tetrahedral arrangement although considerable steric crowding occurs with the smallest metal atoms, as shown in the short contacts present in the dianion [Fe4(CO)i3]2 (6). (The shortest van der Waals contacts between the carbon atoms have been found experimentally to depend strongly on the relative inclination of the carbonyls parallel carbonyls present a minimum distance of 3.0-3.1 A, while this distance decreases to 2.5-2.6 A at the relative angle of 90°-l 10° this effect is clearly related to the expected oval shape of the ligand (I).) Cluster opening occurs by... 

Other examples concern the interaction between iron carbonyles and potassium alkylthiolates that is accompanied by disproportionation. The anion radicals Fe2(CO)g, Fe3(CO)fi, Fe4(CO)i3, and Fe(CO)2 are formed (Belousov et al. 1987). The interaction of iron carbonyls Fe(CO)5, Fe2(CO)9, and Fe3(CO)i2 with (CH3)3NO occurs according to a one-electron redox-disproportionation scheme, giving rise to iron carbonyl anion radicals Fe2(CO)s Fe3(CO)n, l e3(CO)i2, and Fe4(CO)ii (Belousov Belousova 1999). 

Should the free Fe3+ concentration surpass this value due to a better solubility of Iron Blue, then Fe3+ would precipitate as hydroxide and would be increasingly removed from the pigment, thereby destroying it in the end. Since this does not happen at pFI=7 at all, and pH=10 can be considered the point where it just starts to happen, the concentration of the Fe3+ ion in a saturated Iron Blue solution must lie well below 10 18 mol/liter, i. e., in the area of 10"27 mol/liter. Thus, the solubility of Iron Blue must also have a value around 10 27 mol per liter (actually % of the free Fe3+ concentration, Ks less than 4.1 10 187 mol7 l 7, pKs larger than 186.6) which, at a mol mass of 1,110 g mol 1 ((Fe4[Fe(CN)6]3 14 H20) would correlate to 10 24 g. 

The addition of [HS04] [N(n-Bu)4] to the dendrimer 2 provokes the shift of the initial wave that reaches 110 mV at saturation, which leads to an apparent association constant K(+) = (55 5) 103 L Mol The titration diagram shows an equivalence point at 0.75 equiv. [HS04] [N( -Bu)4] per Fe4-cluster branch, although saturation is obtained at 1 equiv. [HS04] [N( -Bu)4] per Fe4-cluster branch. In this case the interaction is of the weak type, loose and not selective. 

Fig. 5. Molecular structure of [Fe3(Se2)2(CO)io][SbF6]2S02 (9). [Reprinted with kind permission from Drake, G. W. Schimek, G. L. Kolis, J. W. The coordination chemistry of cationic main group clusters Syntheses and structures of [Fe3(Se2)2(CO)io]2+ and Fe4 (Se2)3(CO)i2]2 t. Inorg. Chim. Acta 1995, 240, 63. Copyright 1995 Elsevier Science S. A., P.O. Box 564, 1001 Lausanne, Switzerland.]...

Field, L.M. and Devonshire, A.L., Evidence that the E4 and FE4 esterase genes responsible for insecticide resistance in the aphid Myzus persicae (Sulzer) are part of a gene family, Biochem. j., 330, 169,1998. 

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