Infrared laser spectroscopy of the ν2 fundamental band of D2O+

The ν2 fundamental band of D2O+ was recorded in the region 1000-1150 cm−1 using a tunable diode laser spectrometer with velocity-modulation technique. The ions were produced in an ac glow discharge of a mixture of D2O and He. Sixty-four transitions with N ⩽ 11 and K ⩽ 3 were assigned and fitted, yielding a set of improved rotational, spin-rotational and centrifugal distortion constants of the ground and ν2 vibrational states. The ν2 band origin was determined to be 1044.28594(39) cm−1.