10031-26-2Relevant articles and documents
Iron-based catalyst composition for producing oligomers of conjugated dienes
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, (2008/06/13)
A catalyst composition that is the combination of or the reaction product of ingredients comprising (a) (i) a halogen-containing iron compound or (ii) an iron-containing compound and a halogen-containing compound, (b) a silyl phosphonate, and (c) an organoaluminum compound.
About irontribromide: Equilibrium studies, crystal structure, and spectroscopic characterization
Armbruster,Ludwig,Rotter,Thiele,Oppermann
, p. 187 - 195 (2008/10/08)
Iron(III) bromide has been thoroughly characterized by thermal, x-ray, and spectroscopic investigations on crystalline FeBr3 samples which were grown by CVD at higher bromine pressures. The thermodynamical data for equilibria between FeBr2, FeBr3 and Br2 obtained by pressure measurements are in agreement with chemical vapor transport experiments and confirm the statements of the literature to a high extent. Refinement of the crystal structure with single crystal data (a = 6.937(1) ?; c = 18.375(4) ? Z = 6) confirms the assignment to the rhombohedral BiI3 type (Spgr. R-3). On this base, the UV-VIS, FTIR and Raman spectra were interpreted. The totally symmetric stretching mode of FeBr3 (173 cm-1) in comparision to FeCl3 (282cm-1) was found lower as to be expected by consideration of the mass influence alone. Impedance measurements on pure samples under ambient conditions showed low electronic conductivity (10-8Ω-1cm-1) but high capacitive contributions, resulting from displacement polarisation. The investigations gave no hints for neither a mixed valent Fe3Br8 nor a substantial phase width of the solid compounds FeBr2 and FeBr3.
Preparation and spectroscopic characterization of strontium and barium tetrabromoferrate(III) and the crystal structure of Ba(FeBr4)2
Armbruster, Markus,Rotter, Heinz W.,Thiele, Gerhard
, p. 1697 - 1700 (2008/10/08)
The synthesis of the hitherto unknown bromoferrates(III) of alkaline-earth metals was carried out by heating mixtures of the metals or the binary bromides together with bromine at temperatures of 450 °C and pressures of up to 1500 bar in closed quartz ampoules. The attempts have been successful only with the larger cations of Sr and Ba. In the case of Be, Mg, and Ca only mixtures of the binary bromides with FeBr3 could be received. By analysis of the Raman and electronic spectra the dark red compounds of Sr and Ba have been characterized as ternary tetrabromoferrates(III) containing tetrahedral FeBr4 anions. The composition M(FeBr4)2 (M = Sr, Ba) has been determined by potentiometric and titrimetric analysis and thermal degradation by thermogravimetry. A single crystal structure determination of Ba(FeBr4)2 confirmed the spectroscopic assignments. The orthorhombic crystal structure (space group Pbca; a = 13.054(3) A; b = 11.093(2) A; c = 21.764(4) A; Z = 8) consists of FeBr4 and BaBr9 polyhedra.
Standard enthalpies of formation of crystalline iron bromides
Efimov, M. E.,Evdokimova, V. P.
, p. 1224 - 1225 (2007/10/02)
The enthalpies of the reactions of Br2(1), Fe(c), FeBr2(c), and FeBr3(c) with a solution of KBr*0.43Br2*0.12HBr*50.78H2O at 298.15 K have been measured in the dissolution calorimeter with isothermal jacket of the LKB-8700 apparatus.The following values have been calculated from the results: ΔfH0 (FeBr2, c, 298.15 K) = -244.74 +/- 0.22 kJ mol-1, ΔfH0 (FeBr3, c, 298.15 K) = -262.63 +/- 0.20 kJ mol-1.
