Internal dynamics of (H2O)2 and (D2O)2 dimers: III. Description taking into account inversion,exchange and bifurcation motions

Using the symmetry group chain methods, the stationary states of (H₂O)₂ and (D₂O)₂ dimers that correspond to the lowest energy barriers of the inversion, exchange via an intermediate trans configuration, and bifurcation motions are classified taking into account the real geometries of the dimers. A model that rigorously describes the interactions of the motions and leads to a simple algebraic scheme for calculating of both the positions of the levels in the energy spectrum and the intensities of transitions between them is constructed. It is important that the correctness of the model is limited only by the trueness of the choice of symmetry of the internal dynamics.