拉曼光谱的低频振动问题

1. libration means minor swaying motion of a dipole with nearly fixed orientation, 有点像单摆的样子。而vibration则是分子dipole振动时大的orientation的变化。
2. 低频峰大多能帮助读出分子的精确结构，尤其是键所处的化学环境等等，as libration is subject to external forces or constraints that restrict its orientation.