The Spectrum and Term System of P V

The spectrum of quadruply ionized phosphorus has been studied in the wavelength region 200-9 800 Å by using a sliding spark in vacuum. A total of 126 spectrum lines have been measured and classified, 88 of which are new. The term system has been recalculated and new terms added. The polarization formula applied to nf, ng and nh gives an ionization limit of 524 462.9 ± 1.0 cm-1 and a dipole polarizability of the core 2s 22p 6 of 0.0949 a 0 3.