Two-step polarization-labeling spectroscopy of excited states ofNa2

Abstract

Two-step polarization-labeling spectroscopy of diatomic molecules is described. Formulas for relative transition intensities are derived, and their use in determining angular momenta of molecular states is discussed. The experimental apparatus and procedure used to identify twenty-four new ${}_{}{}^1{}_{}{}^{}\Sigma _g^{+}{}_{}{}^{}$, ${}_{}{}^1{}_{}{}^{}\Pi _g^{}{}_{}{}^{}$, and ${}_{}{}^1{}_{}{}^{}\Delta _g^{}{}_{}{}^{}$ states in ${\mathrm{Na}}_2$ are described. The states are identified as low-lying members, $n=3\mathrm{} \mathrm{to} 14$, of several molecular Rydberg series, and the dependence of their properties on principal quantum numbers is shown. These results are extrapolated to yield constants for the ground state of $\mathrm{Na}_2^{}{}_{}{}^{+}$.