Interfaces between Molecular and Polymeric “Metals”: Electrically Conductive, Structure‐Enforced Assemblies of Metallomacrocycles

The design, synthesis, characterization, and understanding of new molecular and macro‐molecular substances with “metal‐like” electrical properties represents an active research area at the interface of chemistry, physics, and materials science. An important, long‐range goal in this field of “materials by design” is to construct supermolecular assemblies which exhibit preordained collective phenomena by virtue of “engineered” interactions between molecular building blocks. In this review, such a class of designed materials is discussed which, in addition, bridges the gap between molecular and polymeric conductors: assemblies of electrically conductive metallomacrocycles. It is seen that efforts to rationally construct stacked metal‐like molecular arrays lead logically to structure‐enforced macromolecular assemblies of covalently linked molecular subunits. Typical building blocks are robust, chemically versatile metallophthalocyanines. The electrical optical, and magnetic properties of these metallomacrocyclic assemblies and the fragments thereof, provide fundamental information on the connections between local atomic‐scale architecture, electronic structure, and the macroscopic collective properties of the bulk solid.