Accurate ab initio study on the A2Π, 14Σ+, 14Π, 24Πand 16Σ+ electronic states of AlO radical including spin-orbit coupling

► Convergence is observed with the basis sets and level of theory. ► Effect on the PECs by core-valence correlation and relativistic corrections is included. ► SO coupling effect is discussed. ► PECs are extrapolated to the CBS limit. ► Spectroscopic parameters of seven Λ-S and 17 Ω states are obtained.