Ground and excited states of the diatomic dianion Cl2(2-)

Metastable excited states of OBr2- and OCl2- dianions

Electronic stabilities, structures, properties, and spectroscopic constants of the halogen oxide dianions OBr2- and OCl2- and their singly charged anions which are of astrophysical and laboratory interests have been studied. The X2Σ states of OBr2- and OCl2- are metastable with PECs having smooth wells with minima located at R=1.859 Å and 1.776 Å, and Coulomb barriers of 40402.54987 cm(-1) and 43746.63462 cm(-1) heights located at RRCB=2.100 Å and 1.922 Å, respectively, both without any vibrational states. While, the B2Σ state of OBr2- and the A2Σ state of OCl2- are metastable with PECs having wells deep enough to suite several bound states, with minima located at Re=1.773 Å and 1.6430 Å, and Coulomb barriers of 191437.45813 cm(-1) and 180550.70294 cm(-1) heights located at RRCB=2.658 Å and 2.4480 Å, with De=1.26470 eV and 1.60837 eV, respectively. The OBr- and OCl- singly charged anions are stable in their ground states. Based on the calculated Frank-Condon factors, it is concluded that metastable excited state OBr2- and OCl2- dianions and ground state OBr- and OCl- singly charged anions can be formed via electron capture processes.