Spectra of centrosymmetric rare earth complexes: Pr3+ (HAPI) single crystal

Abstract

Polarized low‐temperature absorption spectrum of centrosymmetric Pr³⁺–antipyrene tri‐iodide single crystal has been recorded. Electronic transitions to the ¹D₂ and ³P_0,1,2 states have been found to be forbidden. Associated vibronic lines have been analyzed. Lattice, metal–ligand, and ligand internal (such as C=0) modes appear in the spectrum. Crystal field parameters have been evaluated and found to be large. Participation of π electrons in the bonding has been suggested.