The approximate analytical solutions of the Dirac
equations with the reflectionless-type and Rosen–Morse potentials
including the spin–orbit centrifugal (pseudo-centrifugal) term are
obtained. Under the conditions of spin and pseudospin (pspin) symmetry
concept, we obtain the bound state energy spectra and the corresponding
two-component upper- and lower-spinors of the two Dirac particles by
means of the Nikiforov–Uvarov (NU) method in closed form. The special
cases of the s-wave Dirac equation and the non-relativistic limit of Dirac equation are briefly studied.