The Absorption Spectrum of PN between 1000 and 600 Å

Abstract The VUV absorption spectrum of PN obtained by the pyrolysis of P 3 N 5 has been observed using the synchrotron radiation of SUPERACO in Orsay, France. Numerous new Rydberg states have been observed between 600 and 1000 A. They have been classified in Rydberg series converging to ionization energies of 15.712 ± 0.011 eV and 16.675 ± 0.011 eV (in perfect agreement with previous photoelectron values). An ionization limit of 18.8340 ± 0.0063 eV corresponding to the D 2 Σ + state of PN + has been experimentally determined for the first time.