We present as a direct generalization of the recently developed full-potential photoemission theory a relativistic theory for space-filling cell potentials. This theory is based on the well-known one-step model of photoemission. The Dirac equation is solved for space-filling cell potentials, using the relativistic phase functional approach. A practical scheme to calculate the generalized spin-density matrix of the photocurrent is described. The relationship between the new model and the widely used relativistic muffin-tin-like theory, as well as the connection to nonrelativistic full-potential photoemission is discussed. Moreover, a detailed analysis of the angular matrix elements and the selection rules for a single-cell potential in the relativistic and nonrelativistic case are given.

• Received 1 July 1994

DOI:https://doi.org/10.1103/PhysRevB.50.14827