Bond rearrangement in single ionization of water
Note that H2O+ → H2+ + O
is about twice as likely as
D2O+ → D2+ + O, with
HDO+ → HD+ + O in between.
A.M. Sayler et al., AIP 576, 33 (2001)
Electron impact data from:
Straub et al., J. Chem. Phys. 108, 109 (1998)