Chiral Control of Gas-Phase Molecules using Microwave Pulses

Angew Chem Int Ed Engl. 2023 Jul 3;62(27):e202219045. doi: 10.1002/anie.202219045. Epub 2023 Apr 27.

Abstract

Microwave three-wave mixing has emerged as a novel approach for studying chiral molecules in the gas phase. This technique employs resonant microwave pulses and is a non-linear and coherent approach. It serves as a robust method to differentiate between the enantiomers of chiral molecules and to determine the enantiomeric excess, even in complex chiral mixtures. Besides such analytical applications, the use of tailored microwave pulses allows us to control and manipulate chirality at the molecular level. Here, an overview of some recent developments in the area of microwave three-wave mixing and its extension to enantiomer-selective population transfer is provided. The latter is an important step towards enantiomer separation-in energy and finally in space. In the last section, we present new experimental results on how to improve enantiomer-selective population transfer to achieve an enantiomeric excess of about 40 % in the rotational level of interest using microwave pulses alone.

Keywords: Chirality; Chirality Control; Coherent Excitation; Microwave Spectroscopy; Population Transfer.

Publication types

  • Review