The ground and charge-transfer excited states of CoO+

The rotationally resolved, resonant photodissociation spectrum of CoO+ has been obtained for the first time. Transitions from the ground state to two excited electronic states are observed, (5)Phi(5) - (5)Delta(4) and (5)Pi(3), - (5)Delta(4) with electronic origins (T-00) at 16713 +/- 10 cm(-1) and 17588 +/- 10 cm(-1), respectively. The zero point rotational constant of the (5)Delta(4) ground state of CoO+ is found to be B-0" = 0.492 +/- 0.006 cm(-1), resulting in an experimental bond length of r(0)" = 1.65 +/- 10.01 Angstrom. The excited states have longer bond lengths (r(0)' = 1.86 +/- 0.01 Angstrom) consistent with the charge transfer nature of the transition. These results are compared with ab initio predictions. (C) 2000 Elsevier Science B.V. All rights reserved.