Development and validation of an on-the-fly hybrid QM/MM approach to quantitatively address the influence of solvent molecules on the predicted IR and VCD spectra of chiral solutes in polar and apolar solvents.

The advancements made in the last two decades in experimental and computational vibrational circular dichroism (VCD) spectroscopy, the differential absorption of left and right circularly polarized light during a vibrational transition, have established the technique as the most versatile method available today for determining the absolute configuration (AC) of chiral molecules. The connection between the AC of a chiral molecule and its experimental VCD spectrum is established through matching a quantum chemical prediction of the VCD spectrum for a given configuration with the experimental spectrum. Unfortunately, because many substances do not dissolve in desirable concentration or aggregate in apolar solvents, and because spectra of solutions in a polar solvent have to be used instead, the limits of VCD are reached when studying molecules with multiple conformers capable of forming strong intermolecular interactions. To overcome these limitations, and to develop a more robust approach that can be used to quantitatively address the influence of solvent molecules on the IR and VCD spectra of solute molecules, we aim at developing an innovative and ground-breaking integrated on-the-fly combined quantum and molecular mechanical QM/MM hybrid approach that allows the internal dynamics due to conformational changes in the solute and due to the displacements of the nearby solvent molecules on the spectral properties to be accounted for explicitly.

Keywords:MOLECULAR SPECTROSCOPY

Disciplines:Theoretical and computational chemistry, Other chemical sciences

Project type:Collaboration project