Interactions between organic molecules and water:: Rotational spectrum of the 1:1 oxetane-water complex

The 1:1 molecular complex between oxetane and water has been investigated by using free-jet millimeter-wave spectroscopy. The rotational spectra of five isotopomers (with H2O, D2O, DOH, HOD and (H2O)-O-18) have been assigned. Partial r(o) and r(s) structures of the complex have been derived. The water moiety lies in the plane of symmetry of oxetane, with the "free" hydrogen E with respect to the ring. The oxetane ring appears to be slightly nonplanar, with the C carbon tilted on the opposite side of the water unity. The three atoms involved in the hydrogen bond adopt a linear arrangement with an O-ring...H distance of about 1.86 Angstrom, and the angle between the COC bisector and the O-ring...H bond being congruent to106degrees. Additionally, quantum-chemical calculations for the complex were performed and were found to be in agreement with the experimental results.