Stark Field Modulated Microwave Detection of Molecular Chirality

TL;DR

This paper details a microwave technique that uses Stark field modulation to detect molecular chirality by measuring the polarization of emitted radiation, enabling enantiomeric excess determination.

Contribution

It provides a comprehensive theoretical framework and formulas for calculating the expected signal strength in Stark field modulated microwave chiral detection.

Findings

Derived expressions for signal strength in various transitions.

Confirmed the opposite sign of signals for enantiomers.

Established a basis for quantitative chiral analysis using microwave spectroscopy.

Abstract

Patterson, Schnell, \& Doyle, {\it Nature} {\bf 497}, 475 (2013) introduced a microwave experiment that produces a perpendicularly polarized molecular emission when chiral molecules are resonantly excited in the presence of a Stark Field that is then adiabatically switched off before observation of the emission. The sign of the signal is opposite for two stereo-enantiomers and thus the magnitude of the signal gives the enantiomeric excess of the sample. This paper presents a detailed presentation of the theory behind this and provides expressions for the absolute calculation of the expected signal strength for different transitions.