Simultaneous determination of transient free radicals and reaction kinetics by high-resolution time-resolved dual-comb spectroscopy.
Pei-Ling LuoEr-Chien HorngPublished in: Communications chemistry (2020)
Quantitative determination of multiple transient species is critical in investigating reaction mechanisms and kinetics under various conditions. Dual-comb spectroscopy, a comb-laser-based multi-heterodyne interferometric technique that enables simultaneous achievement of broadband, high-resolution, and rapid spectral acquisition, opens a new era of time-resolved spectroscopic measurements. Employing an electro-optic dual-comb spectrometer with central wavelength near 3 µm coupled with a Herriott multipass absorption cell, here we demonstrate simultaneous determination of multiple species, including methanol, formaldehyde, HO 2 and OH radicals, and investigate the reaction kinetics. In addition to quantitative spectral analyses of high-resolution and tens of microsecond time-resolved spectra recorded upon flash photolysis of precursor mixtures, we determine a rate coefficient of the HO 2 + NO reaction by directly detecting both HO 2 and OH radicals. Our approach exhibits potential in discovering reactive intermediates and exploring complex reaction mechanisms, especially those of radical-radical reactions.
Keyphrases
- high resolution
- simultaneous determination
- tandem mass spectrometry
- liquid chromatography tandem mass spectrometry
- ultra high performance liquid chromatography
- high speed
- solid phase extraction
- high performance liquid chromatography
- mass spectrometry
- optical coherence tomography
- liquid chromatography
- cerebral ischemia
- magnetic resonance imaging
- stem cells
- molecularly imprinted
- molecular dynamics simulations
- magnetic resonance
- computed tomography
- carbon dioxide
- electron transfer
- ionic liquid
- molecular dynamics
- bone marrow
- cell therapy
- aqueous solution
- high resolution mass spectrometry
- blood brain barrier