以色列希伯来大学Daniel Strasser团队报道了水合氢离子和氢氧根的相互中和作用。相关研究成果于2024年1月19日发表于国际一流学术期刊《科学》。

水合氢离子（H₃O⁺）和氢氧根离子（OH）的相互中和是一个非常基本的化学反应。然而，关于潜在的反应机制，只有有限的实验证据。

该文中，研究人员报道了低温双静电离子束存储环（DESIREE）中冷离子和孤立离子，在低碰撞能量下相互中和反应的重合中性产物的三维成像。确定了主要的H₂O+OH+H和2OH+H₂产物通道，并将其归因于电子转移机制，而具有高内部激发的H₂O+H₂O的少量贡献归因于质子转移。所报道的机制解析了内积激发，以及碰撞能量和初始离子温度的依赖性，为电荷转移机制的建模提供了基准。

附：英文原文

Title: The mutual neutralization of hydronium and hydroxide

Author: Alon Bogot, Mathias Poline, MingChao Ji, Arnaud Dochain, Ansgar Simonsson, Stefan Rosén, Henning Zettergren, Henning T. Schmidt, Richard D. Thomas, Daniel Strasser

Issue&Volume: 2024-01-19

Abstract: Mutual neutralization of hydronium (H3O+) and hydroxide (OH) ions is a very fundamental chemical reaction. Yet, there is only limited experimental evidence about the underlying reaction mechanisms. Here, we report three-dimensional imaging of coincident neutral products of mutual-neutralization reactions at low collision energies of cold and isolated ions in the cryogenic double electrostatic ion-beam storage ring (DESIREE). We identified predominant H2O + OH + H and 2OH + H2 product channels and attributed them to an electron-transfer mechanism, whereas a minor contribution of H2O + H2O with high internal excitation was attributed to proton transfer. The reported mechanism-resolved internal product excitation, as well as collision-energy and initial ion-temperature dependence, provide a benchmark for modeling charge-transfer mechanisms.

DOI: adk1950

Source: https://www.science.org/doi/10.1126/science.adk1950