title: Monitoring Isomerization of Molecules in Solution Using Ion Mobility Mass Spectrometry.
abstract: An ion mobility spectrometer (IMS) with an electrospray ion source is used to investigate photo and thermal isomerization of photoactive molecules in the electrospray syringe. A light emitting diode adjacent to the syringe establishes a photostationary state that relaxes thermally toward the more stable isomer once illumination ceases. The arrangement is demonstrated by measuring Z-E thermal isomerization rates for several azoheteroarene compounds. The IMS technique has a distinct advantage over UV-vis spectrophotometry for measuring isomer populations in situations where there are multiple isomers with overlapping absorption profiles. In another development, an LED array adjacent to the silica capillary connecting the syringe to the electrospray ion source, is used to activate photochromic molecules, and investigate sequential photoswitching events.
authors.affiliation: School of Chemistry, University of Melbourne , Melbourne, Victoria 3010, Australia.
authors.forename: James N
authors.identifier: 0000-0003-0953-1716
authors.initials: JN
authors.lastname: Bull
authors.affiliation: School of Chemistry, University of Melbourne , Melbourne, Victoria 3010, Australia.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Scholz
authors.affiliation: School of Chemistry, University of Melbourne , Melbourne, Victoria 3010, Australia.
authors.forename: Neville J A
authors.initials: NJ
authors.lastname: Coughlan
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , Ohokayama, Meguro-ku, Tokyo 152-8551, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Kawai
authors.affiliation: School of Chemistry, University of Melbourne , Melbourne, Victoria 3010, Australia.
authors.forename: Evan J
authors.identifier: 0000-0003-1848-507X
authors.initials: EJ
authors.lastname: Bieske