[en] Full text: Persistent luminescence materials can emit light for 24+ h after ceasing the irradiation. They have received special attention due to their versatile applications in emergency signalization, micro defect sensing, and optoelectronics for image storage as well as in high energy radiation detection and pressure/temperature sensing. Prior to commercial applications, detailed and systematic studies of the persistent luminescence mechanisms are required to develop new efficient photonic materials, however. Since 1996 the mechanisms of the Eu²⁺ persistent luminescence phenomenon have attracted the main attention and only relatively few studies have been dedicated to the persistent luminescence phosphors doped with trivalent rare earths (R³⁺) like e.g. Ce³⁺, Pr³⁺ , Eu³⁺ or Tb³⁺. Nevertheless, the study of the optical properties of these luminescent materials with different dopants is expected to contribute significantly to the understanding of the persistent luminescence mechanisms in general. This work investigates the persistent luminescence properties of different R³⁺ doped materials as Lu₂O₃ :Tb³⁺, CaTiO₃ :Pr³⁺ and Cd_nSiO_2+n:R³⁺. The materials were characterized with Infrared Absorption Spectroscopy, X-ray Powder Diffraction, Scanning Electron Microscopy and X-ray Absorption Spectroscopy (XANES and EXAFS) while the luminescence properties were studied with VUV-UV-vis excitation and emission spectroscopy. Finally, the R³⁺ energy level positions were determined based on the ligand to metal charge transfer transitions. Based on experimental data, the mechanisms for the persistent luminescence were determined. It was found that the narrow band gap (≤4 eV) hosts are suitable for Pr³⁺ persistent luminescence whereas Tb³⁺ demands wider band gaps (ca. 5 eV). (author)