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M. A. SUHM, Institut für Physikalische Chemie, Universität Göttingen, D-37077 Göttingen, Germany.
The interaction between pairs of chiral objects such as hands depends on their relative handedness. Pairs of right (or left) hands match better than mixed left/right pairs, and if we enforce the latter, the grip will be a rather different one. Obviously, this macroscopic experience has its counterpart at the molecular level. A molecular dimer built from two identical copies of a chiral molecule will differ from one which is built from mutual mirror copies. One way to detect this phenomenon of chiral self-recognition is via infrared spectroscopy of supersonic jets. Ragout-jet FTIR spectroscopy provides the necessary sensitivity. It allows for the study of small prototype systems, which are also accessible to high level quantum chemistry treatments. Results on glycidol dimer and related systems are presented. They provide unambiguous spectral evidence of chiral self-recognition. The spectra are discussed in terms of conformational flexibility and hydrogen bond topology. An outlook on molecular self-organization in larger aggregates is given.