Multireference configuration interaction (MRCI) potential curves were obtained for six 1A′, 1A′′, 3A′, and 3A′′ states of bromomethylene, HCBr, as functions of RCBr for bond angles of 102.9° and 130°, and as functions of the bond angle for RCBr = 1.8682 Å. Besides the well-known X1A′, a3A′′ and A1A′′ states, 21A′(3.26), 31A′(4.48), 41A′′(5.05), 41A′(5.06), 51A′(5.65), 43A′(6.00), 51A′′(6.60), 61A′′(6.60), 63A′′(6.61) (with estimated upper limits to the adiabatic transition energies in eV in parentheses), as well as several 5s and 6s Rydberg states, were found to be stable or metastable. Estimated spectroscopic constants for bound and metastable states, as well as vertical excitation energies for repulsive or quasi repulsive states are listed. The CH+Br dissociation energy of the ground state is about 3.5 eV, and 3.3 eV for a3A′′, whereas it is about 3.6 eV for CBr–H dissociation. It follows that photodissociation of ground-state HCBr by sunlight (up to 4.4 eV) can lead to both Br and H radicals. Photodissociation via several low-lying states is also possible. PACS Nos.: 31.10.+z, 31.15.Ar, 31.25.–v, 31.25.gf, 31.25.Qm, 31.50.Df, 31.15.Dj, 31.15.Fm
