Optical spectroscopy of RuC: 18 000-24 000 cm ?1

The optical spectrum of diatomic RuC has been recorded from 17 800 to 24 200 cm-1. Three previously unidentified excited electronic states were analyzed and identified as having ?'=0, ?'=2, and V853. The ?'=3 state was determined to be a 3?3 state that is suggested to arise from a mixture of the 10??11?25rr?2??12?16rr1 and 10??11??5rr?2? ?12??6rr1 electronic configurations. Three additional bands belonging to the previously observed [18.1] 1II?X1? system were analyzed to obtain B'e=0.558 244(48) cm-1, ?'e=0.004 655(27) cm-1, ?'e=887.201(37) cm-1, and ?'ex'e=55.589(7) cm-1 for the 102Ru 12C isotopomer (1? error limits). A Rydberg-Klein-Rees analysis was then performed using the determined spectroscopic constants of the [18.1] 1II state, and similar analyses were performed for the previously observed states. The resulting potential energy curves are provided for the 100Ru 12C, 101Ru 12C, 102Ru 12C, and 104Ru 12C isotopic species.