Research into molecular topology has been gaining pace, with chemists increasingly able to manipulate matter at the atomic scale. Now, a team working across the UK, the US, and beyond has pushed that field into genuinely uncharted territory.
Chemists at the University of Manchester, working alongside researchers at IBM, have identified a molecule with a shape that did not previously exist in chemistry. According to the report, the structure is being described as “half-Möbius” — a reference to the looped, one-sided band familiar from mathematics. Where a Möbius strip requires two full circuits to return to a starting point, this molecule demands four. A theoretical quantum traveller moving along its atomic ring would complete four loops before arriving back where it began.
The molecule was built from 13 carbon atoms and two chlorine atoms, assembled into a ring on a gold surface held at extremely low temperature. Two specialised instruments — an atomic force microscope and a scanning tunnelling microscope — allowed the team to both arrange the atoms and map the behaviour of their electrons.
The role of electrons and quantum simulation
The unusual geometry does not come from the atoms themselves but from the electrons surrounding them. In this molecule, electrons are not tightly bound to individual atoms. Instead, they spread across the structure in wave-like patterns, and it is the interactions between those waves that produce the novel topology. Igor Rončević at the University of Manchester described the result as “very new and very unexpected,” stating that “no one really thought about” this shape being possible.
The team also demonstrated control over the structure. By applying a small electromagnetic pulse, they could switch the molecule’s twist from left-handed to right-handed, or remove the twist entirely — engineering its topology on demand.
Simulating why the molecule can exist at all required both conventional computing and an IBM quantum computer. The electron interactions responsible for the shape are difficult to model accurately on standard machines. Quantum computers, built from interacting quantum objects themselves, can handle those simulations with greater confidence, according to team member Ivano Tavernelli at IBM. The work is being cited as a concrete example of quantum computing applied to real chemistry.
Outside perspectives
Gemma Solomon at the University of Copenhagen called it “a remarkable achievement across a number of dimensions: organic chemistry, surface science, nanoscience and quantum chemistry.” Kenichiro Itami at RIKEN in Japan described the study as “a beautiful and inspiring” work that brings “abstract topological concepts vividly into the realm of molecular chemistry.”
Dongho Kim at Yonsei University in South Korea, who has contributed to prior research on Möbius-like molecules, pointed specifically to the switching capability as the most consequential finding. The ability to shift the molecule between shapes could lead to sensor applications — for instance, molecules that switch in a pre-programmed way when exposed to magnetic fields.
The findings have been published in the journal Science under DOI 10.1126/science.aea3321.
This article is a curated summary based on third-party sources. Source: Read the original article
