IR-High resolution spectroscopy of the N2O dimer: The torsional mode

Abstract

The rotational resolved IR-spectrum of the N₂O–N₂O van der Waals complex has been observed in the region of 2244–2252 cm⁻¹ using a computer controlled lead salt diode laser spectrometer. This paper reports on the first observation of a van der Waals mode in (N₂O)₂. 1569 absorption lines could be assigned to the combination of the fundamental ν₃-asymmetric stretch of N₂O-monomer with the ν_tor-van der Waals mode (torsion) of the N₂O-dimer. The band origin of the spectrum is observed at ν₀ = 2247.83 cm⁻¹ which is 20.0 cm⁻¹ above the ν₃ excitation of the N₂O dimer. This deviates considerably from the theoretically predicted value at 37.84 cm⁻¹ (C. Dutton, )