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Updated: Jun 17, 2026
Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyl(tropone)iron
Published on: August 12, 2019
Gas-phase structures of iron trihalides: a computational study of all iron trihalides and an electron diffraction
Zoltán Varga1, Mária Kolonits, Magdolna Hargittai
1Materials Structure and Modeling Research Group of the Hungarian Academy of Sciences, Budapest University of Technology and Economics, P.O. Box 91, 1521 Budapest, Hungary.
Abstract:
The molecular structures of the monomers and dimers of all iron trihalides, FeF(3), FeCl(3), FeBr(3), and FeI(3), were determined by computations, and the structure of iron trichloride monomers and dimers was determined also by gas-phase electron diffraction. The thermal-average bond length, r(g), of FeCl(3) is 2.136(5) A, and the estimated equilibrium bond length from experiment, 2.122(6) A, is in excellent agreement with the computed value. Vibrational and thermodynamic properties have also been calculated for all species. The stability of iron trihalides decreases toward the iodide; neither the bromide nor the iodide can be evaporated without decomposition. The structures of isomers of trimers and tetramers for iron trichloride have also been calculated. The connection between the gas-phase and crystal-phase structures and the exceptional stability of the dimer is discussed.
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