Rotational spectrum, dynamics and bond energy of 2,5-dihydrofuran-krypton van der Waals complex

The equilibrium conformation, dynamics and dissociation energy of the weakly bonded 2,5-dihydrofuran-Kr complex have been deduced from its free jet millimetre-wave spectrum. The equilibrium distance of Kr with respect to the centre of mass of the molecule is 3.61 ?, with Kr tilted 12.8o from the perpendicular to the centre of mass of the ring towards the oxygen atom. The dissociation energy is estimated from the centrifugal distortion constant DJ to be about 3.5kJ mol-1.