Similar to light, electrons exhibit properties of both particles and waves. Those positions are essentially akin to frames that form a motion picture when stitched together, Centurion said. That same laser, which resides at the Stanford University-housed SLAC lab, also triggered a short burst of electrons that raced toward the molecules at nearly the speed of light.Īfter measuring how the electrons diffracted from the laser-excited molecules – and comparing the patterns with those created when electrons struck undisturbed molecules – the researchers managed to calculate sequential positions of the molecules’ atoms.

The researchers induced similar excitations by firing a laser at molecules consisting of two iodine atoms, which share a weak bond that alternately elongates and compresses like a spring when the atoms absorb light. While photosynthesis is considered the classic example, many other reactions regularly serve to help and harm – as when forming protective ozone in the Earth’s atmosphere, for instance, or the ultraviolet rays that cause skin cancer.

Though molecules are always vibrating, light can excite their atoms into different structural configurations that result in photochemical reactions. “That we had not yet demonstrated (until now).” “The main thing we want to see is when the molecular structure is changing,” said co-author Martin Centurion, associate professor of physics and astronomy at the University of Nebraska-Lincoln. Recording this nuclear motion represents a milestone in the quest to produce “molecular movies” that could eventually unveil the dynamics of light-triggered chemical reactions.

3 by the journal Physical Review Letters, the researchers captured the continuous motion of atomic nuclei in vibrating molecules for the first time. Physicists from the University of Nebraska-Lincoln, the SLAC National Accelerator Laboratory and Potsdam University are picking up good vibrations – via laser-driven excitations – after successfully recording the spring-like motion of a two-atom molecule.Īs detailed in a study published Oct.

Nucleus atom