Vacuum Ultraviolet Absorption Spectrum and Dipole Moment of Nitrogen Trifluoride

Abstract

The electronic absorption spectrum of NF₃ was investigated for the first time. At the lowest pressures, the long wavelength limit of absorption is at about 960 A in agreement with the lowest ionization potential of the molecule (939 A). Quantitative intensity measurements showed a smooth decrease of the absorption coefficients to effectively zero at about 1800 A, with no indication of even partly resolved electronic transitions. Comparisons with the electronic spectrum of ammonia are discussed. The molecular dipole moment is used to obtain an equivalent orbital representation of the NF₃ wave function.