Infrared spectra of seeded hydrogen clusters: (para- H ₂) _N-N ₂O and (ortho- H ₂) _N-N ₂O, N=2-13

High-resolution infrared spectra of clusters containing para-H2 and/or ortho-H2 and a single nitrous oxide molecule are studied in the 2225-cm-1 region of the ν1 fundamental band of N2O. The clusters are formed in pulsed supersonic jet expansions from a cooled nozzle and probed using a tunable infrared diode laser spectrometer. The simple symmetric rotor-type spectra generally show no resolved K structure, with prominent Q -branch features for ortho-H2 but not para-H2 clusters. The observed vibrational shifts and rotational constants are reported. There is no obvious indication of superfluid effects for para-H2 clusters up to N=13. Sharp transitions due to even larger clusters are observed, but no definite assignments are possible. Mixed (para- H2) N-(ortho- H2) M-N2O cluster line positions can be well predicted by linear interpolation between the corresponding transitions of the pure clusters.