The optical properties and the natural lifetime calculation of a Sm(III) complex

The photophysical properties of the complex Sm(PM)3(TP)2 [PM = 1-phenyl-3-methyl-4-isobutyryl-5-pyrazolone, TP = triphenyl phosphine oxide] are determined in crystal state, and energy transfer process is modeled for ligands to center Sm(III) ion. The characteristic luminescence of Sm(III) is sensitized by PM and TP, and most of transitions from excited state 4G5/2 of Sm3+ are detected. According to the Judd–Ofelt theory, values of three oscillator strength parameters were obtained. The radiative transition rates for the emission from 4G5/2 to the lower manifolds were obtained, and calculated radiative lifetime of the 4G5/2 manifold is 3.1 ms. The corresponding fluorescence quantum efficiency is 2.7%.