Dynamical symmetry of the quadratic Zeeman effect in hydrogen: Semiclassical quantization

By exploiting the approximate SU(2) symmetry of the m=0 quadratic Zeeman Hamiltonian within multiplets of fixed principal quantum number, the dynamics is mapped onto a twofold hindered rotor. This allows a singularity-free uniform semiclassical quantization of Solov'ev's approximate integral of the motion to be performed. Excellent agreement with quantum results is obtained.