THE STRUCTURE OF NITROUS-OXIDE TETRAMER FROM NEAR-INFRARED LASER SPECTROSCOPY

High resolution infrared spectroscopy has been used in conjunction wit h ab initio calculations to determine for the first time the structure of the nitrous oxide tetramer. We observe a non-planar structure in w hich all four molecules are approximately parallel. The high symmetry of this system makes the spectral assignment straightforward. In fact, the ab initio calculations and experiment indicate that this system i s very nearly a spherical top with rotational constants A '' = B '' = 0.0248 cm(-1) and A' = B' = 0.02495 cm(-1). The C rotational constant can only be roughly estimated to be 0.02 cm(-1) from the relative inte nsities of the Q and P,R branches observed in this C-type band. (C) 19 97 Elsevier Science B.V.