Angle-resolved photoemission is measured on bulk crystals of CuI cleaved in situ. A direct transition regime is observed. The shape of three valence bands is given. Secondary electron emission localizes some conduction-band features. The proposed band scheme assumes characteristic transitions which are effectively observed in the optical spectra we had measured previously. The spin-orbit splitting, observed in two valence bands, permits the evaluation of the mixing rate of iodine and copper orbitals.

• Received 9 June 1987

DOI:https://doi.org/10.1103/PhysRevB.37.3068