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Rotationally-resolved infrared spectra of N 2 O-Ar and N 2 O-Kr van der Waals clusters are studied in the region of the N 2 O ν 1 vibration (≈ 2224 cm −1 ) using a tunable Quantum Cascade laser source to probe a pulsed supersonic jet. The N 2 O-Kr ν 1 fundamental band is re-analyzed, together with previous ν 3 band data, using a unified scheme to fit the (small) observed Kr isotope splittings. This scheme is then transferred to analyze the bending combination band of N 2 O-Kr near 2257 cm −1 where isotope effects are much larger due to stretch-bend Coriolis interactions. As a result, N 2 O-Kr intermolecular bend (33.29 cm −1 ) and stretch (34.48 cm −1 ) frequencies are directly determined for the first time.We also report observation of weak spectra for both N 2 O-Ar and -Kr corresponding to the (ν 1 , ν 2 l2 , ν 3 ) = (1,1 1 ,0) ← (0,1 1 ,0) hot band of N 2 O, located around 2209.8cm −1 . In the presence of Argon/Krypton atom, the doubly-degenerate ν 2 bending mode of the N 2 O monomer splits into an in-plane and an out-of-plane mode. These two infrared bands are heavily linked by Coriolis interactions and their analysis yields the magnitude of the splitting of the bending modes which are significantly smaller than those observed in the analogous CO 2 -containing dimers a . The experimental results obtained here are valuable for testing the accuracy of theoretical calculation toward a better understanding of intermolecular interactions.

Rotationally-resolved infrared spectra of the bending modes of N 2 O-Ar and N 2 O-Kr van der Waals clusters have been studied in the region of the N 2 O ν 1 fundamental vibration (≈ 2224 cm −1 ), using a tunable quantum cascade laser source to probe complexes generated in pulsed supersonic jet expansion. The assigned vibrational transitions are hot bands (1, 1 1 , 0)← (0, 1 1 , 0) observed under supersonic conditions. In the presence of Argon/Krypton atom, the doubly-degenerate ν 2 bending mode of the N 2 O monomer splits to two modes, in-plane and out-of-plane of the complex, with A and A symmetry, respectively. These two infrared bands are heavily linked by Coriolis interaction.Analysis of the two bands for N 2 O-Ar, located about 2209.8 cm −1 with a splitting of ∼0.1 cm −1 between the in-plane and out-of-plane intramolecular bending modes, yields experimental values ξ a = 0.04215and ξ b =0.13646 for a-and b-type Coriolis interaction parameters for the lower state. For the N 2 O-Kr, these values are found to be ξ a = 0.04205 and ξ b =0.09212. The two bands for this complex are located about 2209.5 cm −1 and with a splitting of ∼0.4 cm −1 . Contrary to CO 2 containing complexes, the sign of splitting cannot be determined. This is due to lower symmetry of the N 2 O-rare gas complexes.Coriolis interaction parameters found in these analyses, along with that of the previously-reported bands for CO 2 -Ar a and CO 2 -N 2 b complexes, offer important information for testing the accuracy of theoretical calculation toward a better understanding of intermolecular interactions.