A theoretical study of the radiative transition probabilities and lifetimes of the lowest quartet states of CaN

Accurate potential energy curves, dipole moment functions, dissociation energies and spectroscopic constants for three quartet electronic states (X4Σ−, A4Π and B4Σ−) of the CaN molecule are reported with the multireference singles and doubles configuration interaction methodology. Also, are present radiative transition probabilities and lifetimes for the A4Π–X4Σ−, B4Σ−–X4Σ− and B4Σ−–A4Π band systems. The ground state (X4Σ−) has an equilibrium distance equal to 4.410a0 and the dissociation energy is 0.85 eV. The A4Π has a shorter equilibrium distance equal to 4.142a0 and the B4Σ− has a much longer equilibrium distance, equal to 5.426a0. Radiative lifetimes for v′=0 are predicted to be 27 000, 0.256 and 565 μs for the A4Π–X4Σ−, B4Σ−–X4Σ− and B4Σ−–A4Π band systems, respectively.