Zhao Hang, Tan Yong, Zhang Rui, Zhao Yuejin, Zhang Cunlin, Zhang Liangliang
Opt Lett. 2021 Jan 15;46(2):230-233. doi: 10.1364/OL.409849.
The microscopic mechanism for ionic influence on the hydrogen bond network of water has not been fully understood. Here we employ the terahertz Kerr effect (TKE) technique to map the intermolecular hydrogen bond dynamics in a series of aqueous halide solutions at the sub-picosecond scale. Compared with pure water, the significantly enhanced bipolar TKE response associated with polarization anisotropy in an ionic aqueous solution is successfully captured. We decompose the measured TKE response into different molecular motion modes and demonstrate that the obviously increasing positive polarity response is mainly due to the anion-water hydrogen bond vibration mode with the resonant THz electric field excitation. Our measurement results provide an experimental basis for further insight into the effects of ions on the structure and dynamics of a hydrogen bond in water.
离子对水的氢键网络的微观作用机制尚未完全明晰。在此，我们运用太赫兹克尔效应（TKE）技术，在亚皮秒尺度上描绘一系列卤化盐水溶液中的分子间氢键动力学。与纯水相比，我们成功捕捉到了离子水溶液中与极化各向异性相关的显著增强的双极TKE响应。我们将测得的TKE响应分解为不同的分子运动模式，并证明明显增强的正极性响应主要归因于具有共振太赫兹电场激发的阴离子 - 水氢键振动模式。我们的测量结果为进一步深入了解离子对水中氢键结构和动力学的影响提供了实验依据。
