INVESTIGATION OF CHARGE-TRANSFER O2--]LN3--]LN3+ IN LAF3(LN3+, O2-) AND YF3(LN3+, O2-) SYSTEMS( AND F)

Excitation spectra of the visible luminescence of Eu3+, Dy3+, Er3+ ion s doped into two fluoride matrices, LaF3 and YF3, holding some traces of O2- ions were recorded in the UV and VUV range. Charge transfer ban ds O2- --> Ln3+ (Ln3+ = Eu3+, Dy3+, Er3+) and F- --> Eu3+ appear clear ly on excitation spectra recorded at low temperature. Using the experi mental data and Jorgensen's theoretical developments, it becomes possi ble to predict the energy of charge transfer O2- --> Ln3+ and F- --> L n3+ for all the trivalent ions of the lanthanide series. The time-depe ndent theory was used to simulate the CT absorption profile.