Isomers in the Chemistry of Heterometallic Iron Clusters Part II Heterometallic Trimers

Abstract

The iron heterometallic trimeric clusters constitute a broad field for research, as shown by a recent survey covering the crystallographic and structural parameters of over 600 examples. About 7.5% of these clusters exist as distortion isomers and are summarized. These are discussed in terms of the coordination about the metal atoms, bond lengths and interbond angles. Only distortion isomers cover all the mentioned clusters. Distortion isomers differ mostly by degree of distortion in M-L, M-L-M and L-M-L parameters. There are 15 metal partners with the iron atom, with three categories of trimers (Fe2M(x18), FeM2(x19) and FeMM´(x4)). The shortest metal-metal bond distances are: 2.504(1) Å (Fe-Fe), 2.368(1) Å (Fe-Ni), and 2.288(1) Å (W-W). From the structural point of view, a triangular core of the metal atoms capped by 3 -X (X=S, Cl or PL) is the most common.

Keywords: Iron, Heterometallic trimer, Distortion isomer, Structure