Researchers have observed special relativity altering chemical bonds for the first time in a charged bismuth-carbon molecule. The finding challenges the standard model of sigma and pi bonds. It was achieved through precise electron mapping and theoretical calculations.
Lai-Sheng Wang at Brown University led the team that created the molecule and cooled it to reduce vibrations. They mapped electron distributions and found two bonds mixed sigma and pi characters rather than fitting traditional categories.
Wang stated the bonds differ from normal understanding and cannot be called standard sigma or pi types. Kirk Peterson at Washington State University confirmed through calculations that relativistic speeds of electrons near the bismuth nucleus caused the effect.
Pekka Pyykkö at the University of Helsinki noted the experimental and theoretical methods were optimal. The results may affect uses of organic bismuth compounds in catalysis, building on prior work at the Max Planck Institute for Coal Research.
The team plans further tests with nearby elements on the periodic table. The study appears in Science.