Angular-radial integrability of Coulomb-like potentials in Dirac equations

We consider the Dirac equation, written in polar formalism, presence of general Coulomb-like potentials, that is, potentials arising from time component vector potential and depending only on radial coordinate, order to study conditions integrability, given as some specific form for solution: we find angular dependence can always be integrated, while is reduced finding solution a Riccati equation so it possible, at least principle. exhibit known case Coulomb one special generalization examples show versatility method.