Synthesis and Redox‐Induced Structural Isomerization of the Pentagonal Bipyramidal Complexes [W(CN)₅(CO)₂]³⁻ and [W(CN)₅(CO)₂]²⁻

Abstract

There has been a surge of interest in the use of cyanometalate complexes for the synthesis of magnetic molecules [1] and solids.[2] The variation of the metal electron configuration and coordination geometry enables adjustment of magnetic properties, such as the spin ground state, magnetic anisotropy, and the strength of the exchange coupling. Second-and thirdrow transition-metal ions are of particular interest, owing to a large magnetic anisotropy stemming from spin-orbit coupling, as well as to their diffuse valence d orbitals, which can result in strong magnetic exchange.[3] Owing to poorly understood reactivity patterns and the preference for low-spin electron configurations, however, there are relatively few examples of simple, paramagnetic building units containing these metals. While S = 1/2 complexes, such as [Nb (CN)