The calculated excitation energies are in good agreement with experimental data, which is reflected by the calculated UV-Vis spectra. The results suggest that the lowest-energy excited state in each compound corresponds to a ML-LCT (metal-ligand to ligand charge transfer) state. We constructed Jablonsky diagrams for the luminescence phenom. In (1), this process consists of flourescence originated from the S1 state and the phosphorescence from the T1 state. In (2) the emission energy only results in phosphorescence.
We found mainly differences in the geometrical parameters that envolve the Pd metal. The structural changes observed in the calculated geometries of the first excited states respect to those of the ground state have significative relevance in the values of the calculated Stokes shifts showed by the complexes in their UV-Vis/emission spectra.