Knowledge Bank

We report multireference configuration-interaction calculations for the four lowest adiabatic doublet potential energy surfaces of $CH(X \mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Pi ,A \mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Delta ,B \mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma -,C \mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma +)-Ne (1S)$ open shell van der Waals molecule. The CH-Ne van der Waals complex is found lo be bound by about $30.5cm-1$ in the electronic ground slate with a T-shaped geometry. The A, B, and C state potential energy surfaces have two minima at collinear geometries which correspond to isometric CH-Ne and Ne-CH structures. The dissociation energies for the excited states range from $35cm-1$ to $45cm-1$ ,where the global minima in each excited state can be found at the linear CH-Ne configuration. The calculated potential energy surfaces have been fitted lo an analytical function and used lo calculate bound rovibrational levels of the CH-Ne complex. In order to investigate why $CH(C \mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma +)$-Ne complex was not seen experimentally, we have calculated transition moments for the transition ground state to all there excited states.