© J. van Wijngaarden 2024 York University recognizes that many Indigenous Nations have longstanding relationships with the territories upon which York University campuses are located that precede the establishment of York University. York University acknowledges its presence on the traditional territory of many Indigenous Nations. The area known as Tkaronto has been care taken by the Anishinabek Nation, the Haudenosaunee Confederacy, and the Huron-Wendat. It is now home to many First Nation, Inuit and Métis communities. We acknowledge the current treaty holders, the Mississaugas of the Credit First Nation. This territory is subject of the Dish with One Spoon Wampum Belt Covenant, an agreement to peaceably share and care for the Great Lakes region.

research

Probing the energy landscapes of molecules The energies of molecular motions, such as rotation and vibration, are unique fingerprints of a compound. With support from modern compuational chemistry methods, we apply state-of-the-art ultrahigh resolution spectroscopic techniques to probe the lowest energy motions of molecules. Spectra recorded in the far- infrared region using synchrotron light from the Canadian Light Source provide measures of molecular vibrations with unprecedented detail while our custom- built microwave spectrometers at the University of Manitoba shed light on rotations and molecular re-arrangements. Our research fits under a number of diverse themes including (but not limited to):
Driving forces of conformational equilibria You probably remember from your introductory chemistry classes that molecules can adopt different geometries depending on their arrangement around single and double bonds, but did you know that each form has its own distinct rotational spectrum? For diallylamine , for example, we have shown that there are 42 possible geometries depending on the positions of the two side chains relative to the central NH functional group. We identified spectral fingerprints of the four lowest energy forms and found that the rich conformational mixture is a result of a careful balance of hyperconjugative and steric effects. Astrochemical signatures Did you know that astronomers use microwave and infrared spectra to identify new species in space? We generate potential candidates in the lab such as HCCNCS and HCCCCNCS using high voltage electric discharge sources and record their microwave and infrared spectra for inclusion in astronomy catalogs. Each new detection in space provides another piece in the puzzle of the chemical evolution of the Universe. Accurate molecular geometries Do you know how scientists find the bond lengths and angles of a molecule with great accuracy and precision? They use Molecular Rotational Resonance (MRR) spectroscopy, the electric field analog of NMR spectroscopy. We have two instruments in our lab that allow us to measure even the most subtle changes in molecular geometry. We can even show the preference for one resonance structure over another as in our studies on fluorinated rings of anisole and benzaldehyde . Microsolvation Did you ever consider how the properties of a molecule change when solvent molecules pack around it? Our spectra help us identify the lowest energy binding sites for solvent, which conformers are more easily solvated and the dynamics of the solvent-solute interaction. In our study of the microsolvation of thiophene , for example, we identified two facile tunnelling motions involving the water hopping across the ring and rotating about its symmetry axis.
vW Research Lab
© J. van Wijngaarden 2024

research

Probing the energy landscapes of molecules The energies of molecular motions, such as rotation and vibration, are unique fingerprints of a compound. With support from modern compuational chemistry methods, we apply state-of-the-art ultrahigh resolution spectroscopic techniques to probe the lowest energy motions of molecules. Spectra recorded in the far-infrared region using synchrotron light from the Canadian Light Source provide measures of molecular vibrations with unprecedented detail while our custom-built microwave spectrometers at the University of Manitoba shed light on rotations and molecular re-arrangements. Our research fits under a number of diverse themes including (but not limited to):
Driving forces of conformational equilibria You probably remember from your introductory chemistry classes that molecules can adopt different geometries depending on their arrangement around single and double bonds, but did you know that each form has its own distinct rotational spectrum? For diallylamine , for example, we have shown that there are 42 possible geometries depending on the positions of the two side chains relative to the central NH functional group. We identified spectral fingerprints of the four lowest energy forms and found that the rich conformational mixture is a result of a careful balance of hyperconjugative and steric effects. Astrochemical signatures Did you know that astronomers use microwave and infrared spectra to identify new species in space? We generate potential candidates in the lab such as HCCNCS and HCCCCNCS using high voltage electric discharge sources and record their microwave and infrared spectra for inclusion in astronomy catalogs. Each new detection in space provides another piece in the puzzle of the chemical evolution of the Universe. Accurate molecular geometries Do you know how scientists find the bond lengths and angles of a molecule with great accuracy and precision? They use Molecular Rotational Resonance (MRR) spectroscopy, the electric field analog of NMR spectroscopy. We have two instruments in our lab that allow us to measure even the most subtle changes in molecular geometry. We can even show the preference for one resonance structure over another as in our studies on fluorinated rings of anisole and benzaldehyde . Microsolvation Did you ever consider how the properties of a molecule change when solvent molecules pack around it? Our spectra help us identify the lowest energy binding sites for solvent, which conformers are more easily solvated and the dynamics of the solvent-solute interaction. In our study of the microsolvation of thiophene , for example, we identified two facile tunnelling motions involving the water hopping across the ring and rotating about its symmetry axis.
vW Researh Lab