Overlap integrals and excitation energies calculations in trivalent lanthanides 4f orbitals in pairs Ln-L (L = Ln, N, O, F, P, S, Cl, Se, Br, and I)

In this work, DFT-based calculations of overlap integrals (rho) and excitations energies (Delta epsilon) associated with the diatomic-like pairs Ln(3+)-Ligand and Ln-Ln' are presented. The rho and Delta epsilon quantities are useful for the calculations of overlap polarizability, charge factors, intensity parameters (using the Simple Overlap and Bond Overlap models), 4f shielding factors, and energy transfer process (ligand-to-Ln and Ln-Ln). A comprehensive set of parametric curves of the type exp(a + bR + cR(2)) are presented to easily determine these properties at a given distance R. Some literature is presented to indicate the importance of rho and Delta epsilon quantities in photophysical properties of lanthanide-based compounds.