When molecules collide with surfaces, they exchange energy with the surface atoms. This complex process is influenced by quantum interference, where different pathways overlap, creating patterns where some paths enhance each other while others cancel out. This affects how molecules exchange energy and react with surfaces.

Observing quantum interference in collisions with heavier molecules like methane (CH4) was challenging due to the many possible pathways. Scientists wondered if quantum effects would disappear, making classical physics enough to describe these processes.