Untersuchungen über Iodoferrate: Die Kristallstrukturen von Fe(THE)6(FeI3THF)2 · THF und Fe(Ch2O)6(FeI4)2 · I2(THF = C4H8O)

Investigations about Iodoferrates: The Crystal Structures of Fe(thf)₆(FeI₃thf)₂ · thf and Fe(CH₂O)₆(FeI₄)2 · I₂(thf = C₄H₈O) The crystal structures of FeI₂ · 3 thf (i.e. Fe(thf)₆(FeI₃thf)₂ · thf) ( 1 ) and Fe(CH₂O)₆(FeI₄)₂ · I₂ ( 2 ) were determined from single crystal X-ray data. 1 crystallizes in the cubic space group Pa3, a = 1759.8 pm, Z = 4, 2 in the monoclinic space group P2₁/n, a = 997.4, b = 1669.4, c = 1082.6 pm, β = 93.11°, Z = 2. The structure of 1 is composed of octahedral Fe(thf)₆²⁺ cations and distorted tetrahedral FeI₃(thf)]-anions (Fe? I distance 261.1 pm). In 2 two tetrahedral tetraiodoferrate (III) anions are linked by an iodine molecule. The Fe? I distance was found to be 253.9 pm (mean, the I? I distance between FeI₄^? and I₂ 356.1 pm. The decomposititon of 1 in vacuum at elevated temperatures and the resulting formation of 2 from 1 are discussed.