Finding the thinnest metallic wire

One-dimensional materials have gained an increasing attention in the last decades: from nanotubes to ultrathin nanowires, down to freestanding few-atom atomic chains. One-dimensional materials could display unique electronic properties and great potential for next-generation applications. In this context, exfoliable bulk materials could naturally provide a source for one-dimensional wires with atomically-thin structures. Here, we explore a database we created of one-dimensional materials that could be exfoliated from experimentally known three-dimensional Van-der-Waals compounds. We explore this database searching for metallic wires that are resilient to Peierls distortions and could act as vias or interconnects for future downscaled electronic devices. As the low-dimensional nature makes these wires particularly susceptible to dynamical instabilities, we carefully characterize vibrational properties of prospective candidates in order to identify their stable phases and study their electronic and dynamical properties. Our search identifies novel and stable metallic wires; notably, we discover what could be the thinnest stable metallic wire, CuC₂, coming a step closer to the ultimate limit in materials downscaling.