An international team of researchers from IBM, The University of Manchester, Oxford University, ETH Zurich, EPFL, and the University of Regensburg has synthesized and characterized a molecule with an electronic structure never before observed. Their findings, published in Science on March 5, 2026, detail the creation of a molecule whose electrons travel in a corkscrew-like pattern—a half-Möbius electronic topology.
The molecule, with the formula C₁₃Cl₂, was assembled atom by atom at IBM using a precursor made at Oxford University. Researchers used voltage pulses under ultra-high vacuum and near-absolute-zero temperatures to remove individual atoms. Advanced microscopy techniques developed at IBM enabled them to observe an electronic configuration that undergoes a 90-degree twist with each loop through the molecule’s structure. This means four complete circuits are needed for electrons to return to their original phase.
This half-Möbius topology is distinct from any previously known molecular structures and can be switched between different twisted states. According to the research team, this demonstrates that electronic topology can be engineered intentionally rather than just discovered in nature.
To understand how this unusual molecule behaved at an electronic level required high-fidelity quantum computing simulations. Traditional computers struggle with modeling molecules like C₁₃Cl₂ because of the complex interactions among its electrons—each electron affects all others simultaneously. Quantum computers are better suited for such tasks because they operate according to quantum mechanical laws similar to those governing electrons in molecules.
Alessandro Curioni of IBM Research Zurich said: “First, we designed a molecule we thought could be created, then we built it, and then we validated it and its exotic properties with a quantum computer. This is a leap towards the dream laid out by renowned physicist Richard Feynman decades ago to build a computer that can best simulate quantum physics and a demonstration where, as he said, ‘There’s plenty of room at the bottom.’ The success of this research signals a step towards this vision, opening the door for new ways to explore our world and the matter within it.”
Dr. Igor Rončević from Manchester University explained: “Chemistry and solid-state physics advance by finding new ways to control matter. In the second half of the 20th century, substituent effects were very popular. For example, researchers explored how the potency of a drug or the elasticity of a material changes if, for example, a methyl is replaced with chlorine. The turn of the century brought us spintronics, introducing electron spin as a new degree of freedom to play with, and transforming data storage. Today, our work shows that topology can also serve as a switchable degree of freedom, opening a new powerful route for controlling material properties.
“The non-trivial topology of this molecule, and the exotic behavior of many other systems arises from interactions between their electrons. Simulating electrons with classical computers is very hard – a decade ago we could exactly model 16 electrons; today we can go up to 18. Quantum computers are naturally well-suited for this problem because their building blocks – qubits – are quantum objects which mirror electrons. Using IBM’s quantum computer we were able to explore 32 electrons. However,the most exciting part is this is just the start. Quantum hardware is advancing rapidly,andthe future is quantum.”
Dr Harry Anderson from Oxford University noted: “It is remarkable that the Lewis structure of C₁₃Cl₂ already indicates it is chiral as confirmed by experiment and quantum chemical calculations.Itis also amazing that enantiomers can be interconverted by applying voltage pulses fromthe probe tip.”
Dr Jascha Repp from UniversityofRegensburg added:“I’m really excitedtobe partofaprojectwherequantumhardwaredoesrealscience notjustdemos.It’s fascinating thata tinymoleculecanhavesuchacomplexelectronicstructurethatischallengingtosimulateclassically,andisso twistedandstrangethatitalmosttwistsyourmind.”
The research builds on IBM’s history in nanoscale science including inventions such as scanning tunneling microscopy (STM), which allows scientists to image surfaces atom-by-atom since its invention at IBM in 1981.
For more information about this project visit Quantum simulates properties of the first-ever half-Möbius molecule designed by IBM and researchers.
