A chirped-pulse Fourier-transform microwave/pulsed uniform flow spectrometer. II. Performance and applications for reaction dynamics
- 5 December 2014
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 141 (21), 214203
- https://doi.org/10.1063/1.4903253
Abstract
This second paper in a series of two reports on the performance of a new instrument for studying chemical reaction dynamics and kinetics at low temperatures. Our approach employs chirped-pulse Fourier-transform microwave (CP-FTMW) spectroscopy to probe photolysis and bimolecular reaction products that are thermalized in pulsed uniform flows. Here we detail the development and testing of a new K(a)-band CP-FTMW spectrometer in combination with the pulsed flow system described in Paper I [J. M. Oldham, C. Abeysekera, B. Joalland, L. N. Zack, K. Prozument, I. R. Sims, G. B. Park, R. W. Field, and A. G. Suits, J. Chem. Phys. 141, 154202 (2014)]. This combination delivers broadband spectra with MHz resolution and allows monitoring, on the μs timescale, of the appearance of transient reaction products. Two benchmark reactive systems are used to illustrate and characterize the performance of this new apparatus: the photodissociation of SO2 at 193 nm, for which the vibrational populations of the SO product are monitored, and the reaction between CN and C2H2, for which the HCCCN product is detected in its vibrational ground state. The results show that the combination of these two well-matched techniques, which we refer to as chirped-pulse in uniform flow, also provides insight into the vibrational and rotational relaxation kinetics of the nascent reaction products. Future directions are discussed, with an emphasis on exploring the low temperature chemistry of complex polyatomic systems.Funding Information
- National Science Foundation (MRI-ID 1126380)
This publication has 39 references indexed in Scilit:
- Extension of the measurement, assignment, and fit of the rotational spectrum of the two-top molecule methyl acetateJournal of Molecular Spectroscopy, 2014
- The rotational spectrum of methyl ethyl ketone in its ground vibrational stateJournal of Molecular Spectroscopy, 2014
- An arbitrary waveform generator based chirped pulse Fourier transform spectrometer operating from 260 to 295GHzJournal of Molecular Spectroscopy, 2012
- Rotational spectroscopy of 2-methylfuran from 8.7 to 960GHzJournal of Molecular Spectroscopy, 2012
- Room temperature chirped-pulse Fourier transform microwave spectroscopy of anisoleJournal of Molecular Spectroscopy, 2011
- Rotational spectroscopy of iodobenzene and iodobenzene–neon with a direct digital 2–8GHz chirped-pulse Fourier transform microwave spectrometerJournal of Molecular Spectroscopy, 2011
- Design and evaluation of a pulsed-jet chirped-pulse millimeter-wave spectrometer for the 70–102 GHz regionThe Journal of Chemical Physics, 2011
- Chirped-pulse terahertz spectroscopy for broadband trace gas sensingOptics Express, 2011
- Measuring Picosecond Isomerization Kinetics via Broadband Microwave SpectroscopyScience, 2008
- A broadband Fourier transform microwave spectrometer based on chirped pulse excitationReview of Scientific Instruments, 2008