10min:
ENCAPSULATION OF WATER MOLECULES BY DIBENZO-18-CROWN-6-ETHER IN A SUPERSONIC JET.

R. KUSAKA, Y. INOKUCHI, K. KAWASAKI AND T. EBATA, Department of Chemistry, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, 739-8526, Japan.

UV and IR spectra of jet-cooled Dibenzo-18-crown-6-ether (DB18C6) and DB18C6-(H2O)n are observed by laser induced fluorescence (LIF), UV-UV hole-burning and IR-UV double resonance spectroscopy . The LIF spectrum exhibited complicated vibronic structure in the region of 35500-36800 cm-1. The UV-UV hole-burning and IR-UV double resonance spectra suggest the existence of two conformers for DB18C6; one is "boat-type" structure having C2v symmetry, and the other is "chair-type" structure having Ci symmetry. For the hydrated clusters, we assigned most of them to the "boat-type" DB18C6-(H2O)_n=1-4. Details of the encapsulation structure in DB18C6-(H2O)_n=1-4 will be discussed by the comparison of the observed IR spectra with those obtained by quantum chemical calculation.