  For zero energy, $E=0$, we derive exact, quantum solutions for {\it all}
power-law potentials, $V(r) = -\gamma/r^{\nu}$, with $\gamma > 0$ and $-\infty
< \nu < \infty$. The solutions are, in general, Bessel functions of powers of
$r$. For $\nu > 2$ and $l \ge 1$ the solutions are normalizable; they
correspond to states which are bound by the angular-momentum barrier.
Surprisingly, the solutions for $\nu < -2$ are also normalizable, They are
discrete states but do not correspond to bound states. For $2> \nu \geq -2$ the
states are unnormalizable continuum states. The $\nu=2$ solutions are also
unnormalizable, but are exceptional solutions. Finally, we find that by
increasing the dimension of the \seq beyond 4 an effective centrifugal barrier
is created, due solely to the extra dimensions, which is enough to cause
binding. Thus, if $D>4$, there are $E=0$ bound states for $\nu > 2$ even for
$l=0$. We discuss the physics of the above solutions are compare them to the
classical solutions of the preceding paper.
