title: The multiplexed chemical kinetic photoionization mass spectrometer: a new approach to isomer-resolved chemical kinetics.
abstract: We have developed a multiplexed time- and photon-energy-resolved photoionization mass spectrometer for the study of the kinetics and isomeric product branching of gas phase, neutral chemical reactions. The instrument utilizes a side-sampled flow tube reactor, continuously tunable synchrotron radiation for photoionization, a multimass double-focusing mass spectrometer with 100% duty cycle, and a time- and position-sensitive detector for single ion counting. This approach enables multiplexed, universal detection of molecules with high sensitivity and selectivity. In addition to measurement of rate coefficients as a function of temperature and pressure, different structural isomers can be distinguished based on their photoionization efficiency curves, providing a more detailed probe of reaction mechanisms. The multiplexed three-dimensional data structure (intensity as a function of molecular mass, reaction time, and photoionization energy) provides insights that might not be available in serial acquisition, as well as additional constraints on data interpretation.
authors.affiliation: Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, USA. dlosbor@sandia.gov
authors.forename: David L
authors.initials: DL
authors.lastname: Osborn
authors.forename: Peng
authors.initials: P
authors.lastname: Zou
authors.forename: Howard
authors.initials: H
authors.lastname: Johnsen
authors.forename: Carl C
authors.initials: CC
authors.lastname: Hayden
authors.forename: Craig A
authors.initials: CA
authors.lastname: Taatjes
authors.forename: Vadim D
authors.initials: VD
authors.lastname: Knyazev
authors.forename: Simon W
authors.initials: SW
authors.lastname: North
authors.forename: Darcy S
authors.initials: DS
authors.lastname: Peterka
authors.forename: Musahid
authors.initials: M
authors.lastname: Ahmed
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Leone