Chemphyschem. 2003 Jun 16;4(6):541-8. doi: 10.1002/cphc.200200536.

Search for resolution of chiral fluorohalogenomethanes and parity-violation effects at the molecular level.

Chemphyschem : a European journal of chemical physics and physical chemistry

Jeanne Crassous, Franck Monier, Jean-Pierre Dutasta, Michaël Ziskind, Christophe Daussy, Christophe Grain, Christian Chardonnet

PMID: 12836475 DOI: 10.1002/cphc.200200536

Abstract

The first observation of a parity-violation effect in molecules induced by weak interactions is still a dream that requires the synthesis and, eventually, the resolution of the enantiomers of well-chosen simple chiral molecules together with an appropriate experimental set-up for high-resolution spectroscopy. Performing IR spectroscopy on highly enantiomerically enriched samples of bromochlorofluoromethane succeeded in giving an upper limit of 10(-13) for the relative vibrational energy difference between the two enantiomers. These results led us to conceive a new experimental set-up based on a supersonic molecular beam and to work on other chiral molecules, such as chlorofluoroiodomethane. A synthesis of (+/-)-CHCIFI from racemic chlorofluoroiodoacetic acid should, in the near future permit the preparation of optically active samples of this haloform. The development of molecular beam spectroscopy using a two-photon Ramsey-fringes experiment should allow us to reach the precision needed to observe parity violation. These experimental challenges, which stimulate a close collaboration between chemists and physicists, are presented. The success of these projects would open the route to new information on the molecular Hamiltonian, a better knowledge of the electroweak interaction, and a better control of the various chirality-related properties of simple molecules.

Publication Types

• Journal Article