Symmetry method for the absolute determination of energy-band dispersions E(k) using angle-resolved photoelectron spectroscopy.

Angle-resolved spectra for emission in a mirror plane as a function of emission angle and photon energy hν show critical-point behavior in interband intensities for transitions on zone boundaries. For such transitions, the absolute energies E and crystal momentum k→ for both the initial and final states are given by hν and the emission angle. E(k→) dispersions have been determined for several d bands and conduction bands along the Δ, Λ, and Î axes of copper. © 1978 The American Physical Society.