GHz repetition rate mid-infrared frequency comb spectroscopy of fast chemical reactions Journal Article uri icon

Overview

abstract

  • Molecular diagnostics are a primary tool of modern chemistry, enabling; researchers to map chemical reaction pathways and rates to better; design and control chemical systems. Many chemical reactions are; complex, involving multiple species and reaction pathways occurring on; µs or shorter timescales. Existing diagnostic approaches provide a; subset of chemical and thermodynamic information. Here we optimize; across many diagnostic objectives by introducing a high-speed and; broadband, mid-infrared dual-frequency-comb absorption spectrometer.; The optical bandwidth of >1000cm−1 covers absorption fingerprints of; many species with spectral resolution <0.03cm−1 to accurately discern their absolute; quantities. Key to this advance are 1 GHz pulse repetition rate; mode-locked frequency combs covering the 3–5 µm region that enable a; spectral acquisition rate of 290cm−1 per 17.5 µs per detector for in situ tracking of fast chemical process; dynamics. We demonstrate this system to quantify the abundances and; temperatures of each species in the complete reactants-to-products; breakdown of 1,3,5-trioxane, which exhibits a formaldehyde; decomposition pathway that is critical to modern low-temperature; combustion systems. By maximizing the number of observed species and; improving the accuracy of temperature and concentration measurements,; this spectrometer provides a pathway for modern chemistry approaches; such as combining chemical models with machine learning to constrain; or predict complex reaction mechanisms and rates.

publication date

  • June 20, 2024

has restriction

  • gold

Date in CU Experts

  • June 26, 2024 2:52 AM

Full Author List

  • Hoghooghi N; Chang P; Egbert S; Burch M; Shaik R; Diddams SA; Lynch P; Rieker GB

author count

  • 8

published in

Other Profiles

Electronic International Standard Serial Number (EISSN)

  • 2334-2536

Additional Document Info

start page

  • 876

end page

  • 876

volume

  • 11

issue

  • 6