We have measured 43 transitions centered at 1972 cm− 1 in the (011)–(001) bending hot band of the azide ion (N− 3) using diode laser velocity modulation spectroscopy of an NH3/N2O discharge. The data, ranging from P (32) to R (40), were fit to a standard l??type doubling Hamiltonian through quartic terms. The l splittings in the spectrum were unusually large compared with similar molecules. Intensity measurements indicate that the ...
