Nuclear spins are widely assumed to play a passive ‘spectator’ role in chemical reactions. State-resolved measurements of ultracold Rb–KRb collisions now reveal that these spins are active participants in the collisional dynamics — posing new challenges for theoretical methods and offering fresh insight into the mysteriously ‘sticky’ collisions of ultracold molecules.

中文翻译：

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核自旋在超冷原子-分子碰撞中活跃


人们普遍认为核自旋在化学反应中起着被动的“旁观者”角色。超冷 Rb-KRb 碰撞的状态分辨测量现在表明，这些自旋是碰撞动力学的积极参与者——对理论方法提出了新的挑战，并为超冷分子神秘的“粘性”碰撞提供了新的见解。