Vibrational analysis of the green-yellow system of La¹⁸O

Using a low-pressure arc source the band spectrum of La 18 O has been obtained. The heads between 5200-6300 AA were analysed and the vibrational constants are: sigma e =17884.89 cm -1 , omega e '=696.00 cm -1 , omega e ' chi e '=1.83 cm -1 , omega e "=775.53 cm -1 , and omega e " chi e "=2.06 cm -1 . With these figures the recalculated positions of the bands are in excellent agreement with the experimental values.