Semiclassical expectation values for relativistic particles with spin 1/2

Fore relativistic particles with spin 1/2, which are described by the Dirac equation, a semiclassical trace formula is introduced that incorporates ex pectation values of observables in eigenstates of the Dirac-Hamiltonian. Fu rthermore, the semiclassical limit of an average of expectation values is e xpressed in terms of a classical average of the corresponding classical obs ervable.