Morse Potential Parameters for O–O, N–N, and N–O Interactions

Abstract

Morse potential parameters are determined for the atom‐atom interactions corresponding to the following states having potential minima: the ${\mathrm{X\hspace{0.17em}}}^3{\Sigma }_g^{-}{,}^1{\Delta }_g{,}^1{\Sigma }_g^{+}{,}^3{\Delta }_u{\mathrm{,\; \hspace{0.17em}A\hspace{0.17em}}}^3{\Sigma }_u^{+}{,}^1{\Sigma }_u^{-}$ , and B ³Σ_u⁻ states of O–O (or molecular oxygen); the ${\mathrm{X\hspace{0.17em}}}^1{\Sigma }_g^{+}{\mathrm{,\; A\hspace{0.17em}}}^3{\Sigma }_u^{+}{\mathrm{,\; B\hspace{0.17em}}}^3{\Pi }_g{\mathrm{,\hspace{0.17em}a\hspace{0.17em}}}^1{\Pi }_g\mathrm{,\hspace{0.17em}}\mathrm{and}{\mathrm{\hspace{0.17em}C\hspace{0.17em}}}^3{\Pi }_u$ states of N–N (or molecular nitrogen); and the ${\mathrm{X\hspace{0.17em}}}^2{\Pi }_{\frac{1}{2}}{\mathrm{,\hspace{0.17em}X\hspace{0.17em}}}^2{\Pi }_{\text{3/2}}{\mathrm{,\hspace{0.17em}B\hspace{0.17em}}}^2{\mathrm{\Pi ,C\hspace{0.17em}}}^2{\mathrm{\Pi ,D\hspace{0.17em}}}^2{\Sigma }^{+}{\mathrm{,\hspace{0.17em}B\prime }}^{\text{\hspace{0.17em}2}}{\mathrm{\Delta ,\hspace{0.17em}E\hspace{0.17em}}}^2{\Sigma }^{+}$ , and A ²Σ⁺ states of N–O (or nitric oxide). For the nitric oxide excited A, D, and E ²Σ⁺ states, a unique assignment of dissociation products and unique energies of dissociation were obtained by supposing that these three states have the same shape for their potential energy curves. Previously Barrow and Miescher had made this assumption only for the A and D ²Σ⁺ states and they obtained two possible interpretations. Our analysis suggests the possibility of an unobserved ²Σ⁺ excited state of NO having a potential minimum 2454 cm⁻¹ above the minimum for the D ²Σ⁺ state. This new state should dissociate into a ground state nitrogen atom and a (2s) ²(2p) ³(3p) ³P oxygen atom.