Description of the full picture of nonrigid motions of nonexchange type in the hydrazine molecule N2H4

On the basis of the methods of symmetry, a combined description of four nonrigid motions of the nonexchange type, connecting eight independent energetically equivalent equilibrium configurations of the hydrazine molecule N2H4, is obtained. It is important that the description contains a procedure for constructing the effective operators of physical quantities characterizing the molecule and the space of wave functions, in which these operators are defined. A necessary set of equilibrium configurations is specified with the help of the coordinate spin operators. In particular, this allows one to solve the problem of separating the internal rotation and rotation of the molecule as a whole, which is here sufficiently nontrivial. It is shown that the presence of nonrigid motions of the nonexchange type leads to a dynamic group of symmetry for the problem in the Born-Oppenheimer approximation and, as a consequence, to the appearance, in this approximation, of nonsymmetric representations for the effective Hamiltonian.