Spectroscopic Studies and Crystal-Field Analyses of Am3+: LiYF4

Abstract

Fluorescence and laser selective excitation spectroscopy have been used to investigate the electronic energy level structure of the actinide Am3+(5f6) in LiYF4. From the analysis of the fluorescence in the visible and infrared spectra obtained at 10 K, 29 crystal-field levels have been assigned in theD2dapproximation. Zeeman splitting observation permits one to index some doubly degenerated Γ5levels. The phenomenological crystal-field parameters have been calculated in theD2dapproximation. A least-square adjustment yields a mean error of 38 cm−1with the following values (in cm−1) of theBkqparameters:B20=473,B40=−1776,B44=−2253,B60=80, andB64=−2222.