On the calculation and interpretation of covalency in the intensity parameters of 4f–4f transitions in Eu3+ complexes based on the chemical bond overlap polarizability

authors	Renaldo T. Moura Jr., Albano N. Carneiro Neto, Ricardo L. Longo, Oscar L. Malta
nationality	International
journal	Journal of Luminescence
abstract	The concepts of chemical bond overlap polarizability (αOP) and of specific ionic valence (υ) were used to characterize the Eu3+–ligating atom bonds in complexes. The underlying chemical bond properties, namely, bond distance, overlap integral, force constant, and the energy excitation, were successfully calculated for the Eu3+–ligating atom diatomic-like species under the influence of the molecular environment. The quantities αOP and υ were used to reshape and reinterpret the expressions of the forced electric dipole (FED) and the dynamic coupling (DC) mechanisms responsible for the intensity parameters of4f–4f transitions. These parameters were calculated with this new approach for a series of Eu3+ complexes: [EuL3L′] with L = AIND, BIND, TTA, BTFA, FOD, ABSe, ABSeCl, DPM and L’ = (H2O)2, NO3, DPbpy, DBSO, TPPO, Phen, for which the experimental intensity parameters and some E00 (=5D0-7F0) energies areavailable.Comparisons between the theoretical and experimental results suggest that this new methodology is reliable and an important step toward an approach to calculate the 4f–4f intensities free of adjustable parameters, which has been accomplished for complexes without aquo ligand.
year published	2016
volume	170
beginning page	420
ending page	430
digital object identifier (doi)	10.1016/j.jlumin.2015.08.016