Chiral Rotational Spectroscopy

Abstract

We introduce chiral rotational spectroscopy, a technique that enables the determination of the orientated optical activity pseudotensor components B XX , B Y Y , and B ZZ of chiral molecules, in a manner that reveals the enantiomeric constitution of a sample and provides an incisive signal even for a racemate. Chiral rotational spectroscopy could find particular use in the analysis of molecules that are chiral solely by virtue of their isotopic constitution and molecules with multiple chiral centers. A basic design for a chiral rotational spectrometer together with a model of its functionality is given. Our proposed technique offers the more familiar polarizability components α XX , α Y Y , and α ZZ as by-products, which could see it find use even for achiral molecules.

Chiral optical fields: a unified formulation of helicity scattered from particles and dichroism enhancement

“…Chiral fields are acquiring increasing attention due to their potential as probes of matter at the nanoscale [1][2][3][4][5][6][7][8][9], of which life molecules are of paramount importance, or as high information capacity signals in communication channels [8,[10][11][12][13] with control and transfer of angular momentum, which includes recently developed structured materials and metasurfaces. The conservation of the electromagnetic helicity of wavefields (or, equivalentely, chirality when they are quasi-monochromatic; we shall indistinctly use both terms for such fields) [4,6,14,15] was recently shown [16] to lead to a new optical theorem which characterizes the excitation and emission of field helicity -or chirality-by bodies, and that we believe should play a growing relevant role in coming years with the progress of research on applications of twisted light.…”

“…Chiral fields are acquiring increasing attention due to their potential as probes of matter at the nanoscale [1][2][3][4][5][6][7][8][9], of which life molecules are of paramount importance, or as high information capacity signals in communication channels [8,[10][11][12][13] with control and transfer of angular momentum, which includes recently developed structured materials and metasurfaces. The conservation of the electromagnetic helicity of wavefields (or, equivalently, chirality when they are quasi-monochromatic; we shall 2017 The Author(s) Published by the Royal Society.…”

Chirality and the angular momentum of light

“…If the chirally sensitive contribution to the interaction energy is for a particular initial rotational state and instead for a final rotational state, where B XX =− G XX ′/ ω +( A Y , ZX − A Z , XY )/3, etc., are molecule-fixed combinations of the optical activity polarizability components and f ≠ i , f ≠ i and f ≠ i in general, then the associated energy difference between the states is which can be observed as part of a light-induced shift in the rotational resonance frequency of such molecules. This chiral rotational spectroscopy promises a number of exciting capabilities, including the ability to determine oriented chiroptical information, determine enantiomeric excess, probe the molecular chirality of racemates, detect and characterize isotopic molecular chirality, and distinguish well and in a chirally sensitive manner between even slightly different molecular forms [100]. …”

Probing Molecular Chirality of Ground and Electronically Excited States in the UV-vis and X-ray Regimes: An EOM-CCSD Study

“…An emerging chiral rotational spectroscopy exploits dichroism effects using microwave (MW-CD) radiation. [7][8][9] Chirality can also be probed by transitions to the continuum, as done in photoelectron circular dichroism. 10,11 The key step in contemporary use of spectroscopy for chiral discrimination is the simulation of the spectra for an a priori chosen absolute configuration of the chiral species.…”