Researchers have been in the hunt to shrink electronic devices, even down to a few molecules. Molecular wires help push toward this reality, and a new type was just developed by researchers at Tokyo Institute of Technology.

The molecular wire is “doped” with organometallic ruthenium, which can achieve a higher conductance than its predecessors. Data gathered from a scanning tunneling microscopy confirmed these results.

Getting down to the specifics, the molecular wire was a “metal electrode-molecule-metal electrode (MMM) junction including a polyyne, an organic chain-like molecule, ‘doped’ with a ruthenium-based unit Ru(dppe)2,” according to Tokyo Institute of Technology.

The design was based on the conducting orbitals’ energy levels of the wire’s atoms.

The reason for its improved conductivity lies within its foundations—the conductive properties fundamentally differ from similar molecular devices, especially the MMM junctions derived from orbital splitting.  

“In other words, orbital splitting induces changes in the original electron orbitals of the atoms to define a new ‘hybrid’ orbital facilitating electron transfer between the metal electrodes and the wire molecules,” according to Tokyo Institute of Technology.

Researchers have seldom seen that orbital splitting behavior from other MMM junctions.

After further investigation into the wire’s conductive properties and its unique qualities, future molecule-sized electronic devices could one day utilize these components.

More details are offered in the article, “’Doping’ of Polyyne with an Organometallic Fragment Leads to Highly Conductive Metallapolyyne Molecular Wire,” published in the Journal of the American Chemical Society.