  The Dirac equation in spherically symmetric fields is separated in two
different tetrad frames. One is the standard cartesian (fixed) frame and the
second one is the diagonal (rotating) frame. After separating variables in the
Dirac equation in spherical coordinates, and solving the corresponding
eingenvalues equations associated with the angular operators, we obtain that
the spinor solution in the rotating frame can be expressed in terms of Jacobi
polynomials, and it is related to the standard spherical harmonics, which are
the basis solution of the angular momentum in the Cartesian tetrad, by a
similarity transformation.
