Scientists at Stanford’s SLAC National Laboratory have gotten an unprecedented glimpse of a chemical bond being born. The researchers used an X-ray laser to show a rare transition state in which two atoms begin to bond.

Anders Nilsson, a SLAC professor who led the research, noted that this discovery represents a critical advance in the study of chemical reactions.

“This is the very core of all chemistry. It’s what we consider a Holy Grail, because it controls chemical reactivity,” Nilsson said. “But because so few molecules inhabit this transition state at any given moment, no one thought we’d ever be able to see it.”

The experiments were conducted at SLAC’s Linac Coherent Light Source (LCLS) facility. Researchers used the LCLS to examine the reaction that neutralizes carbon monoxide in a catalytic converter. Using X-rays, the researchers observed carbon monoxide and oxygen molecules interact and detected changes in the atoms’ electron arrangements – the signs of a chemical bond being born.

The discovery has the potential to prompt further research in reaction transition states.

“This is a super-interesting avenue for theoretical chemists,” said report co-author Frank Abild-Pedersen. “It’s going to open up a completely new field.”

Contact Michael Gioia at mgioia2 ‘at’ stanford.edu.