  A new mechanism is proposed for the magnetization reversal of molecular
nanomagnets such as \Fe8. In this process the spin tunnels from the lowest
state near one easy direction to the first excited state near the opposite easy
direction, and subsequently decays to the second easy direction with the
emission of a phonon, or it first emits a phonon and then tunnels to the final
state. This mechanism is the simplest imaginable one that allows magnetization
relaxation in the presence of a longitudinal magnetic field that is so large
that the nuclear spin environment cannot absorb the energy required for energy
conservation to hold. It is proposed as a way of understanding both
magnetization realaxation and Landau-Zener-St\"uckelberg experiments. The
requisite Fermi golden rule rate, and the spin-flip rates are calculated, and
it is found that these rates are much too low by several orders of magnitude.
Thus the understanding of magnetic relaxation in the experiments remains an
open question.
