‘Molecular surgery’ snips off a single atom

A single hydrogen atom has been snipped off a molecule and then added back on again, marking the first time a single chemical bond has been broken and reforged in a controlled, reversible way.

The researchers used a scanning tunnelling microscope (STM) for their cutting tool, which works by manoeuvring a sharp metal tip close to an object, applying a small voltage, and measuring the trickle of electrons that flow between the two.

The team first used their STM to locate a methylaminocarbyne (CNHCH3) molecule that was fixed to a platinum surface.

Then they turned up the voltage, increasing the flow of electrons. That was enough to break one bond – between the molecule’s nitrogen and hydrogen atom – but not to disturb any of the other bonds, leaving a molecule of methylisocyanide (CNCH3).

Source: New Scientist.