It is commonly assumed that recognition and discrimination of chirality, both in nature and in artificial systems, depend solely on spatial effects. However, recent studies have suggested that charge redistribution in chiral molecules manifests an enantiospecific preference in electron spin orientation. We therefore reasoned that the induced spin polarization may affect enantiorecognition through exchange interactions. Here we show experimentally that the interaction of chiral molecules with a perpendicularly magnetized substrate is enantiospecific. Thus, one enantiomer adsorbs preferentially when the magnetic dipole is pointing up, whereas the other adsorbs faster for the opposite alignment of the magnetization. The interaction is not controlled by the magnetic field per se, but rather by the electron spin orientations, and opens prospects for a distinct approach to enantiomeric separations.
Bibliographical noteFunding Information:
We thank A. Brandis for performing the HPLC measurements. Y.P. and R.N. acknowledge the support of the John Templeton Foundation. R.N. acknowledges the support of the Israel Science Foundation and the European Research Council under the European Union’s Seventh Framework Program (FP7/2007–2013)–ERC grant agreement n° 338720 CISS. Y.P. acknowledges the support of the Israel Science Foundation and the Ministry of Science Israel. O.B.D. acknowledges support from the Israeli Ministry of Science, Technology, and Space, grant number 0399174. L.T.B. acknowledges institutional support from the Institute of Physics Polish Academy of Sciences.
© The Authors.