The rovibrational spectrum of O2-N2O van der Waals complex is measured in the ν1 symmetric stretch region of N2O monomer using a tunable diode laser spectrometer. The complex is generated by a slit-pulsed supersonic expansion with gas mixtures of O2, N2O, and He. Both a- and b-type transitions are observed. The effective Hamiltonian for an open-shell complex consisting of a diatomic molecule in a 3Σ electronic state and a closed-shell partner is used to analyze the observed spectrum. Molecular constants in the vibrationally excited state are ...
