Photodetachment photoelectron spectroscopy shows isomer-specific proton-coupled electron transfer reactions in phenolic nitrate complexes.
Qinqin YuanZiheng ZhangXiangtao KongZicheng LingHanhui ZhangLongjiu ChengXue-Bin WangPublished in: Communications chemistry (2024)
The oxidation of phenolic compounds is one of the most important reactions prevalent in various biological processes, often explicitly coupled with proton transfers (PTs). Quantitative descriptions and molecular-level understanding of these proton-coupled electron transfer (PCET) reactions have been challenging. This work reports a direct observation of PCET in photodetachment (PD) photoelectron spectroscopy (PES) of hydrogen-bonded phenolic (ArOH) nitrate (NO 3 - ) complexes, in which a much slower rising edge provides a spectroscopic signature to evidence PCET. Electronic structure calculations unveil the PCET processes to be isomer-specific, occurred only in those with their HOMOs localized on ArOH, leading to charge-separated transient states ArOH •+ ·NO 3 - triggered by ionizing phenols while simultaneously promoting PT from ArOH •+ to NO 3 - . Importantly, this study showcases that gas-phase PD-PES is a generic means enabling to identify PCET reactions with explicit structural and binding information.
Keyphrases
- electron transfer
- high resolution
- single molecule
- nitric oxide
- drinking water
- low dose
- molecular dynamics
- emergency department
- molecular docking
- healthcare
- radiation induced
- density functional theory
- molecular dynamics simulations
- solid state
- radiation therapy
- dna binding
- brain injury
- mass spectrometry
- subarachnoid hemorrhage
- binding protein
- health information
- visible light