Paramagnetic resonance spectrum of metastableP2atomic nitrogen

The paramagnetic resonance spectrum of metastable ${}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$ atomic nitrogen has been observed downstream from an electrodeless discharge in nitrogen-helium gas mixtures. The $g$ factors for the nine observed transitions deviate significantly from the Lande formula. Analysis of the Zeeman effect shows that the departure from Lande formula is caused by an intermediate Paschen-Back effect which occurs in magnetic fields of only a few kilogauss. The nuclear hyperfine structure has been analyzed (for the ${}_{}{}^{14}{}_{}{}^{}\mathrm{N}$ nucleus) and coupling parameters determined. The fine-structure interval for the ${}_{}{}^2{}_{}{}^{}P$ states has been measured to be 12 970±80 MHz.