Knowledge Bank

Data from recent infrared and resonance fluorescence analyses have been used to determine an equilibrium geometry and potential function through quartic terms for the ground electronic state of $NO2$, using (a) the conventional perturbation expansion Hamiltonian, and (b) the non-rigid bender $Hamiltonian1$ to fit virtual spin-free vibration-rotational term values. The latter Hamiltonian reproduces the term values of states with N $\le$; 10, K $\le$; 5,and $V2$ $\le$; 3 to within $0.02cm-1$. The fit to higher vibrational levels and the ability of the Hamiltonians to reproduce the spectra of Isotopically substituted molecules will be discussed. $$\begin{array}{l@{\hspace{30pt}}l} \multicolumn{1}{c}{r_e = 1.1946 {\AA}} &\multicolumn{1}{c}{\theta_e = 113.89^{\circ}} \ f_{rr} = 10.9061 \mbox{ md/{\AA}} &f_{rrr} = - 90.9110 \mbox{ md/{\AA}}^2\ f_{rr^{\prime}} = 1.9354 \mbox{ md{\AA}} &f_{rrr^{\prime}} = -3.2048\mbox{ md/{\AA}}^2\ f_{r\theta} = 0.4819 \mbox{ md/rad} & f_{rr\theta} = 0.1439 \mbox{ md/{\AA} rad}\ f_{\theta\theta} = 1.6101 \mbox{ md {\AA}/rad}^2 & f_{rr^{\prime} \theta} = -1.2355 \mbox{ md/{\AA} rad}\ & f_{r\theta\theta} = -2.2691 \mbox{ md/rad}^2 \ & f_{\theta\theta\theta} = -2.1170 \mbox{ md\AA/rad}^3 \end{array}$$ $$\begin{array}{l} f_{rrrr} = 526.3816 \mbox{ md/{\AA}}^3\ f_{rrrr^{\prime}} = 5.4794\mbox{ md /{\AA}}^3\ f_{rrr^{\prime} r [FIGURE]