The VUV spectroscopy of deuterated hydrazine, N 2D 4

Abstract

The VUV absorption spectrum of N 2D 4 has been measured in the spectral region 1050–2100 Å using synchrotron radiation. The spectrum, which is largely unstructured, gradually rises from a threshold of 2630 Å and is dominated by three broad peaks of increasing magnitude at ≈ 1940, 1685 and 1400 Å followed by a drop in the absorption at ≈ 1340 Å and then a monotonic rise to the low-wavelength experimental cutoff at 1050 Å. The spectrum can be interpreted either in terms of Rydberg excitations of the nonbonding nitrogen electrons with the broad features resulting from spectral congestion or alternatively, the broad nature of the spectrum may be due to absorption of molecular valence states involvingσ ∗←n and σ ∗←σ transitions. Mulliken proposed the existence of such valence transitions by analogy with corresponding feature in the isoelectric diatomic halogen molecules.