Molecular alignment and chirality in gaseous streams and vortices

The discovery of collisional mechanisms, leading to aligned molecules in gaseous streams, opened the way to the research of possible origin of chiral discrimination involving aligned reactants in molecular dynamics. Experimental evidence is being provided that translational-rotational motions (such as those occurring in vortices), in the liquid phase first and in the gas phase more recently, show manifestations of chiral effects, revealing interesting relations with scenarios on the emergence of chiral selectivity. In this account, we also report the results of experiments of enantiomeric enrichment induced on chiral rotamers by rotational-translational motion. Several chiral molecules were expanded in supersonic seeded molecular beams and the vortex motion was generated by two molecular drag pumps with a right- and a left-handed screw motion, respectively. Connections can be established with many processes occurring in the Universe (and thus possibly related to a prebiotic context), like the stellar accretion of low-mass stars like the Sun and the flowing in atmospheres of rotating bodies. © 2013 Accademia Nazionale dei Lincei.