Synchronized infrared lasers steer molecular shape changes

Scientists at the Fritz Haber Institute’s Molecular Physics and Physical Chemistry departments have demonstrated that two tightly synchronized infrared (IR) laser pulses can steer molecules as they switch between distinct structural conformations. By timing the pulses with sub‑femtosecond precision, the team was able to selectively populate specific excited states, effectively guiding the molecules along desired reaction pathways.

The experiment, which involved a series of ultrafast pump–probe measurements, revealed how the synchronized IR beams influence the potential energy surface that governs the conformational change. These findings provide a new experimental handle on the microscopic dynamics that underlie chemical reactions, offering insights that could inform the design of more efficient catalysts and photonic devices.

The study opens a promising avenue for controlling chemical reactivity with light, illustrating the power of coherent laser techniques to probe and manipulate molecular motion at the quantum level.