Intermolecular potential and rovibrational states of the H2O-D2 complex

► The interaction between H2O and H2 is of great astrophysical interest. ► The rovibrational states of H2O-D2 were computed on an ab initio potential surface. ► Results are compared with the rovibrational states of H2O-H2 computed recently. ► We measured the high-resolution infrared spectrum of H2O-D2 in the H2O bend region. ► Comparison with the calculations provides information on H2O-H2 potential surface.