Abstract
Approximate polaron effective-mass trial functions are constructed to describe 2P hydrogenic polaron levels in weak magnetic fields. Breakdown of the effective-mass description due to level crossing of the 2P effective-mass states with 1S one-phonon states [denoted (1S,1)] necessitates admixture of (1S,1) states to the initial effective-mass state in order to achieve lowest cariational energy. The effect of mixing in the (1S,1) states is to produce, effectively, a double-values 2P energy and to reduce considerably the linear Zeeman splitting near the point of level crossing. Level crossings with (1S,n) states for n>1 are expected, on the basis of a heuristic argument, to produce similar discontinuities near the respective crossing energies. Perturbation theory is used to find expressions in the weak-coupling limit for the Zeeman splitting in the limit of weak binding, and, for stronger binding, near the (1S,1) level crossing.