14 October 2015

Tweaking molecular structure to tune chemical reactivity

A recent high-field EPR study by MagLab users from Wayne State and Grand Valley State Universities has demonstrated that minor changes in the periphery of a nickel-containing molecule can lead to a dramatic reorganization of its electron distribution. This in turn, induces a major shift in the reactivity of this compound.

What did scientists discover?

A small structural change on the edge of a molecule led to a dramatic alteration of both its shape and the position of electrons within the molecule. Stated more precisely, a minor structural modification induced the transfer of one extra electron onto the metal atom. This electron transfer, in turn, leads to a dramatic change in the chemical reactivity of this molecule.

Why is this important?

The position of each electron in a molecule (the electronic structure) determines not only its properties such as color and/or magnetism, but also its ability to react with other molecules. By creating new reactivity, scientists hope to create new catalysts that are able to facilitate chemical transformations that are now difficult or impossible to control with our present-day knowledge. Design of future catalysts relies on establishing correlations between the electronic structure at the metal atom and chemical reactivity.

Who did the research?

B. R. Reed1, S. A. Stoian2, R. L. Lord3, Stanislav Groysman1

1Wayne State University; 2National High Magnetic Field Laboratory; 3Grand Valley State University

Why did they need the MagLab?

THE TOOLS THEY USED

This research was conducted in the 17 T Electron Paramagnetic Resonance Magnet and Spectrometer at the MagLab's EMR Facility.

Measuring the electronic structure of the Nickel-containing complex shown in the figure required high-magnetic-field and high-microwave-frequency (more than 400 GHz) Electron Paramagnetic Resonance spectra that can only be obtained at the MagLab. Spectra recorded at lower fields and lower microwave frequencies using commercial instruments would result in spectral lines that overlap and, thus, cannot be resolved. The high magnetic fields and high microwave frequencies are required to unambiguously determine the electronic structure in the molecule that governs its reactivity and suitability as a future catalyst.

Details for scientists

Funding

This research was funded by the following grants: Boebinger (NSF DMR-1157490), Lord (NSF CHE-1039925), Groysman (NSF CHE-1349048)


For more information, contact Stephen Hill.

Details

  • Research Area: Chemistry
  • Research Initiatives: Materials
  • Facility / Program: EMR
  • Year: 2015
Last modified on 16 October 2015