The structure and rotationally resolved autodetachment spectrum of H15NO– and H14NO– near 3000 cm−1

Abstract

The rotationally resolved vibrational autodetachment spectrum of the H¹⁵NO^– anion has been observed in the region from 2932 to 3092 ${\mathrm{cm}}^{-1}$. ${{}^{r}R}_K\left(N\right)$ branches were observed for $K=4$ through 8, and two ${{}^{r}Q}_K\left(N\right)$ branches with $K=5$ and 6 were assigned. The ${{}^{r}Q}_5\left(N\right)$ branch of H¹⁴NO^– has also been identified. The new observations have allowed a rotational analysis of H¹⁵NO^– and have required a re-analysis of the previously observed spectrum of H¹⁴NO^–. The spectra are consistent with a ground state ($r_m^{\left(1\right)}$) geometry of $r_{\mathrm{NH}}=1.099\AA$, $r_{\mathrm{NO}}=1.330\AA$, and $\angle HNO={105.5}^{°}$, in good agreement with the results of Ellis and Ellison for the NO bond length and comparing well with recent theoretical treatments of this anion. The band has been reassigned as the $\left(0,2,0\right)-(0,0,0)$ band.