Brown chemists find Einstein’s relativity reshapes triple bonds in heavy elements like bismuth

Brown University researchers report direct experimental evidence that classic triple-bond theory breaks down for heavy elements. Using photoelectron spectroscopy, they found that carbon-bismuth bonds show relativistic behavior that blurs the usual distinction between sigma and pi bonds.

The findings suggest chemistry models for heavy elements may need refinement, especially where relativistic effects strongly influence electron behavior. Better understanding these bonds could affect future work in materials science, catalysis, and heavy-element chemistry.