  We have found a new class of time dependent partial waves which are solutions
of time dependent Schr\"odinger equation for three dimensional harmonic
oscillator. We also showed the decomposition of coherent states of harmonic
oscillator into these partial waves. This decomposition appears perticularly
convenient for a description of the dynamics of a wave packet representing a
particle with spin when the spin--orbit interaction is present in the
hamiltonian. An example of an evolution of a localized wave packet into a torus
and backwards, for a particular initial conditions is analysed in analytical
terms and shown with a computer graphics.
