High sensitivity ICLAS of H218O in the region of the second decade (11 520-12 810 cm−1)

The rovibrational assignment was performed on the basis of the results of variational calculations and allowed for assigning 3659 lines to the H216O, H218O, H217O, HD16O and HD18O species, leaving only 1.7% unassigned transitions. A line list including 1712 transitions of H218O has been generated and assigned leading to the determination of 692 rovibrational energy levels belonging to a total of 16 vibrational states, 386 being newly observed. A deviation on the order of 25% has been evidenced for the average intensity values given by HITRAN and the results of variational calculations. Ninety two transitions of the HD18O isotopologue could also be assigned and the corresponding upper rovibrational levels are given.