Influence Spatial Degeneracy on Rotational Spectroscopy Three Wave Mixing and enantiomeric state separation of Chiral Molecules

TL;DR

This paper investigates how spatial degeneracy affects three-wave mixing and enantiomeric separation in chiral molecules, providing optimized pulse sequences and analyzing their effectiveness.

Contribution

It introduces calculations for pulse flip angles considering spatial degeneracy, enhancing the understanding of enantiomeric state separation techniques.

Findings

Q - Q - Q cycles are less effective at higher quantum numbers.

Transition cycles including R, Q, P branches show modest signal reduction.

Spatial degeneracy impacts the efficiency of three-wave mixing processes.

Abstract

Pulse flip angles are calculated for three wave mixing, three state cycles of chiral molecules to produce optimized free induction decay amplitudes proportional to the enantiomeric excess of a sample, and to produced optimized degree of state specific enantiomeric separation. These calculations account for the spatial degeneracy of the levels involved and the resulting inhomogeneous distribution of transition dipole moments. It is found that cycles of transitions that include R followed by Q followed by P branch transitions display only modest reductions of the calculated optimal signals if spatial degeneracy is ignored. Transitions cycles P - Q - R are only slightly worse, while the Q - Q - Q cycles are much worse, increasingly so as the rotational total quantum number increases.