Ab initio potential curves for the X2Σu+, A2Πu and B2Σg+ states of Ca2+

► Accurate ab initio potential energy curves of the X2Σu+,A2Πu and B2Σg+ states of the Ca2+ dimer. ► The B2Σg+ state has a double well character. ► Determination of spectroscopic constants for all the states. ► Calculation of transition dipole moments, radiative lifetimes, static polarizabilities and van der Waals dispersion coefficients.