通过对1750厘米特征峰进行振动分析揭示水中的中间水合质子。

Unveiling the intermediate hydrated proton in water through vibrational analysis on the 1750 cm signature.

作者信息

Yang Xuanye, Wu Yu, Deng Siyu, Liu Ling, Zhao Hongwei, Gao Yi, Liu Chungen

机构信息

Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of the Ministry of Education (MOE), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China.

出版信息

Nat Commun. 2025 Jul 1;16(1):5764. doi: 10.1038/s41467-025-60794-2.

DOI:10.1038/s41467-025-60794-2

PMID:40593601

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC12214643/

Abstract

Hydration of proton is the key to understand the acid-base chemistry and biochemical processes, for which the Zundel and Eigen cations have been recognized as the foundation. However, their dominance remains contentious due to the challenge of attributing the infrared signature at ~1750 cm, stemming from the theoretical dilemma of balancing structural diversity and solvent fluctuations. Herein, we circumvent this obstacle by devising an integrated approach for computing frequency-specific vibrational vectors via inverse Fourier transform of the vibrational density of states. When applied to aqueous acid, it unveils an additional "Intermediate" configuration, linked to the aforementioned spectral signature, which exhibits a higher population (44%) and longer lifetime (51 fs), compared to Zundel-like (28%, 25 fs) and Eigen-like (28%, 36 fs), benefitting from the local electric field induced by surrounding solvent molecules.

摘要

质子水合作用是理解酸碱化学和生化过程的关键，其中祖德尔（Zundel）阳离子和艾根（Eigen）阳离子被视为基础。然而，由于在~1750 cm处红外特征的归属存在挑战，源于平衡结构多样性和溶剂波动的理论困境，它们的主导地位仍存在争议。在此，我们通过设计一种综合方法来规避这一障碍，该方法通过对态密度的振动进行傅里叶逆变换来计算特定频率的振动矢量。当应用于水合酸时，它揭示了一种额外的“中间”构型，与上述光谱特征相关联，与类祖德尔构型（28%，25飞秒）和类艾根构型（28%，36飞秒）相比，该构型具有更高的丰度（44%）和更长的寿命（51飞秒），这得益于周围溶剂分子诱导的局部电场。