LAUSR

Significance No reported material both is intrinsically porous and conducts electricity like a metal. This incompatibility appears to be rooted in the fundamental mechanisms responsible for metallic charge transport. Here, we identified one class of materials, namely, metal–organic frameworks, to be well-suited for the search of intrinsically porous metals. The porous framework Ln1.5(2,3,6,7,10,11-hexaoxytriphenylene) (Ln = La, Nd) is metallic, as seen from electrical conductivity measurements and theoretical calculations. As additional proof, this system hosts a state exclusive to metals known as a charge density wave. We believe that this combination of properties will serve as an important milestone in the study of unconventional conductors and provide a flexible platform for the study of more complex physics in metal–organic frameworks.