Toxic Gas & Icy Cobwebs: How Hydrogen Cyanide May Have Sparked Life on Earth

Researchers at Sweden's Chalmers University of Technology report that toxic hydrogen cyanide (HCN) may have helped create the “seeds of life” on Earth. In computer models of cold environments, HCN freezes into solid crystals whose multi-faceted tips act as mini “cobweb” reactors. These icy facets are highly reactive, enabling chemical pathways not normally possible in such cold conditions. The researchers say these reactions could have started a cascade that gave rise to several building blocks of life. Cobweb crystals drive unexpected reactions According to the paper, the Chalmers team (Marco Capelletti, Hilda Sandström and Martin Rahm) modelled a stable HCN crystal as a 450-nanometre-long cylinder with a multifaceted gem-like tip. This shape matches cobweb-like structures seen in experiments. The simulations identified two surface pathways that convert HCN into hydrogen isocyanide – a more reactive isomer – over minutes to days, depending on temperature. This suggests that even in icy settings, HCN could yield polymers, amino acids and nucleobases. Implications for life and future tests