ERC Consolidator Grant

Mass Spectrometry of Isomeric Ions (IsoMS)
ERC Consolidator Grant (ERC, 2016 - 2021)

This project combines modern mass spectrometric approaches and unique cryo-trapping experiments to investigate structure and properties of reactive species. We study short-lived ionic species that cannot be studied by other known methods. In particular, we aim to establish (cryogenic) ion spectroscopy as an alternative analytical method to characterize short-lived reactive species. We focus on reactive hypervalent metal complexes from the field of biomimetic chemistry.

In the method development, we focus on two directions:

(1) The unparalleled advantage of ESI-MS is its high sensitivity to low-abundant and reactive species. The pertinent question at the heart of all reaction mechanism investigations via MS is how the ions found in the gas-phase relate to the condensed-phase reaction. To address this question we use “Delayed Reactant Labelling”, which directly links condensed phase kinetics to the abundance of isolated gaseous ions.

(2) We aim to expand the portfolio of the methods available to study ions in a cryogenic trap. We will combine cryo-trapping of the ions with their ion mobility separation and with the probing or the stored ions by reactive collisions with neutral molecules.

The upper figure shows an approach to study reactive species in our laboratory:

  • Monitoring species formed in solution.
  • Alternative gas-phase preparation of reactive species.
  • Characterization of isolated mass-selected ions (i.e., with known elemental composition) by their IR spectra and interpretation based on theoretical calculations.
  • Separation of IR spectra of isomers by two-photon technique.

As a result, we were the first to characterize analogous iron(IV)oxo biomimetic complexes in intermediate- and high-spin state.

IsoMS has started here and has build up knowledge on many so far elusive reactive complexes in biomimetic chemistry. To this end, we develop many new techniques how to manipulate these complexes.