北京大学Xin-Zheng Li等合作发现了水三聚体的扭转隧穿裂分现象。2022年11月9日，国际知名学术期刊《美国化学会杂志》发表了这一成果。

利用对核的全维量子方法和一种新的第一性原理水势能面，研究人员证明了水三聚体中的扭转隧穿裂分可以以高达~1 cm^-1的精度再现。研究人员量化了非相邻阱间核量子态的耦合常数，并证明了它们是光谱中四分裂能级从1:2:1的间距中移开的主要原因。

研究人员表示，该研究证明了用简化模型（如Hückel模型）进行处理的局限性，并强调了该系统中量子相互作用的非局域性质。通过诸如从头算等方式，研究人员检验了所得的水势能面的质量，并为以前所未有的精度破译实验光谱提供了更严格的计划，且对更一般的系统更普适。

附：英文原文

Title: Torsional Tunneling Splitting in a Water Trimer

Author: Yu-Cheng Zhu, Shuo Yang, Jia-Xi Zeng, Wei Fang, Ling Jiang, Dong H. Zhang, Xin-Zheng Li

Issue&Volume: November 9, 2022

Abstract: Using a full-dimensional quantum method for nuclei and a new first-principles water potential, we show that the torsional tunneling splitting in a water trimer can be reproduced with accuracy up to ～1 cm–1. We quantify the coupling constants of the nuclear quantum states between nonadjacent wells and show that they are the main reason for shifting the quartet-split levels in spectra from a 1:2:1 spacing. This demonstrates the limitation of treatments using simplified models such as the Hückel model and emphasizes the nonlocal nature of the quantum interactions in this system. With such an ab initio endeavor, we examine the quality of the water potential developed and provide a rigorous scheme to decipher the experimental spectra with unprecedented accuracy, which is applicable to more general systems.

DOI: 10.1021/jacs.2c09909

Source: https://pubs.acs.org/doi/10.1021/jacs.2c09909