Magnetic-Susceptibility Anisotropy, Molecular g Value, and Molecular Quadrupole Moment of 15N15N16O

The high‐field rotational Zeeman effect has been observed in ¹⁵N¹⁵N¹⁶O to give an absolute value of the molecular $g$ value of $\text{g⊥\hspace{0.17em}=\hspace{0.17em}0.07606\hspace{0.17em}±\hspace{0.17em}0.0001}$ and an anisotropy in the magnetic susceptibility of ${\mathrm{\chi \perp \hspace{0.17em}-\hspace{0.17em}\chi }}_{\Vert }{\text{\hspace{0.17em}=\hspace{0.17em}(1.68\hspace{0.17em}±\hspace{0.17em}0.02)\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−29}}\mathrm{ergs}/{\mathrm{G}}^2$ . Arguments are given which show conclusively that the molecular $g$ value is negative. The molecular quadrupole moment in the center‐of‐mass coordinate system is ${\text{Q‖\hspace{0.17em}=\hspace{0.17em}−\hspace{0.17em}(3.65\hspace{0.17em}±\hspace{0.17em}0.25)\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−26}}{\mathrm{esu·cm}}^2$ . The values of the second moment of the electronic charge distribution in NNO are ${\mathrm{〈\Vert ;}}^2{\text{〉\hspace{0.17em}=\hspace{0.17em}23.9\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−16}}{\mathrm{cm}}^2$ and ${\mathrm{〈\perp }}^2{\text{〉\hspace{0.17em}=\hspace{0.17em}3.0\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−16}}{\mathrm{cm}}^2$ . The results are compared with similar results for CO₂, O₂, and N₂.