Knowledge Bank

Potential energy curves for the three lowest states of HNO have been computed using many-body perturbation theory. The electronic energy calculations predicting an $X1A\prime \to a3A\prime \prime$ transition energy equal to 0.85 ev. 19.7 Kcal $mole-1$, and an $X1A\prime -A1A\prime \prime$ transition energy equal to 1.57 eV, 36.2 kcal $mole-1$. The dissociation energy for HNO in the ground electronic state is predicted to be 47.7 kcal $mole-1$, which compares favorably with the experimental value 48.6 kcal $mole-1$. No barrier is found for dissociation from the ground state, but barriers are found for dissociation from both excited states.