Optical spectrum, crystal field analysis of Pr3+ in YPO4

An optical investigation of pr(3+) (1 at.%) in YPO4 single crystal is repor ted. The aim is an improvement of the crystal field analysis by the means o f direct configuration interaction between the ground 4f(2) configuration a nd the nearest excited configurations. The crystal field is analyzed in the theoretical D-2d site symmetry with and without configuration interaction. The results for the associations 4f(2), 4f(2) + 4f5d, 4f(2) + 4f6p and 4f( 2) + 4f5d + 4f6p are compared. The 4f(2) + 4f5d + 4f6p configuration intera ction gives the smallest r.m.s. deviation between experimental and calculat ed energy levels, lowering it from 23.9 cm(-1) on the basis of the 91 4f(2) levels only, down to 5.8 cm(-1), when calculated on the basis of the 315 4 f(2) + 4f5d + 4f6p levels. (C) 2001 Elsevier Science B.V. All rights reserv ed.