Ab initio investigation on the valence and dipole-bound states of CNa− and SiNa−

CNa− and SiNa− have been studied by the CAS-ACPF method. The 3Σ− ground states have binding energies of 5420 and 7517 cm−1, respectively. The 5Σ− excited states are 494 and 1551 cm−1 above the respective ground states. The 1Δ , 3Π , and 1Π valence-excited states for SiNa− should be at least metastable. CNa− and SiNa− possess dipole-bound 5Σ− and 3Σ− states. Binding energies of these states in CNa− are 217 and 236 cm−1, respectively. SiNa− has two stable 5Σ− dipole-bound states, whose binding energies are 246 and 118 cm−1, respectively.