Conformer Selection by Matter-Wave Interference

Abstract

We establish that matter-wave diffraction at near-resonant ultraviolet optical gratings can be used to spatially separate individual conformers of complex molecules. Our calculations show that the conformational purity of the prepared partial beams can be close to 100% and that all molecules remain in their electronic ground state. The proposed technique is independent of the dipole moment and the spin of the molecule and thus paves the way for structure-sensitive experiments with hydrocarbons and biomolecules, such as neurotransmitters and hormones, which have evaded conformer-pure isolation so far.

Otto Stern’s Legacy in Quantum Optics: Matter Waves and Deflectometry

“…Several spectroscopy setups have been proposed in the context of the OTIMA experiment, including multi-photon recoil and polarizability spectroscopy [112]. In the far-field diffraction experiment, a near-resonant ultraviolet optical grating could potentially be used for efficient sorting of conformers [111]. It has also been proposed to employ optical helicity fringes to create a diffraction grating that discriminates chiral enantiomers [123].…”

Conformer Selection by Electrostatic Hexapoles: A Theoretical Study on 1-Chloroethanol and 2-Chloroethanol

“…With resonant photoelectron spectroscopy, Huang et al [29,30] developed a method to obtain information on conformation-selection regarding dipolar molecular radicals by dipole-bound excited states of the corresponding anions cooled in a cryogenic ion trap. Brand et al [31] proposed a technique for conformer selection independent of the dipole moment and the spin based on matter-wave diffraction.…”

Enantiomer superpositions from matter-wave interference of chiral molecules

“…Matter-wave interference is a versatile tool for testing the quantum superposition principle with large molecules [22,36] and for measuring molecular properties in the gas phase [37][38][39]. In addition, far-field matterwave interferometry combined with spatial filtering has been proposed for sorting conformers [40] and enantiomers [41,42] from a racemic mixture. In this article, we achieve three important goals: First, we demonstrate that far-field diffraction from a standing-wave grating together with a handedness-dependent phase shift from an optical helicity grating can be used to prepare enantiomeric superposition states of individual thermally rotating molecules.…”

“…1. At the source, the molecular centre-of-mass state is uncorrelated with the internal degrees of freedom and described by Gaussian smeared point sources [40]. The ro-vibrational degrees of freedom are in a thermal state of temperature of 4 K and with the Hamiltonian (4).…”

“…The grating transformation operators can be calculated in the eikonal approximation [40,41,44]. For molecules with negligible absorption this yields t…”