Metastable and scattering states of a diatomic beryllium molecule

The calculations of vibration-rotation bound states and new metastable states of a diatomic beryllium molecule important for laser spectroscopy are presented. The problem is solved using the potential curve and the authors' software package that implements the iteration Newton method and the high-accuracy finite element method. The efficiency of the proposed approach is demonstrated by calculating vibration-rotation bound states and, for the first time, rotation-vibration metastable states with complex- valued energy eigenvalues (with negative imaginary parts of the order of (10-20 ÷ 6) cm-1) in a diatomic beryllium molecule. The existence of these metastable states is confirmed by calculating the corresponding scattering states with real-values resonance energies.