Electronic Structure and Optical Properties of the Adducts of Er3+ and Yb3+ Thenoyltrifluoracetonate with TPPO

Adducts of Er 3+ and Yb 3+ tris-thenoyltrifluoroacetonate with triphenylphosphine oxide OP(C 6 H 5 ) 3 (TPPO) are studied by X-ray photoelectron spectroscopy, optical spectroscopy, and density functional quantum chemical simulations. The spatial structure, electronic levels, effective atomic charge distribution, and excited states are simulated. The main physicochemical characteristics are established from experimental photoelectronic and optical absorption spectra. The experimental data are interpreted using the obtained theoretical results. According to the calculations, all the excited states are caused by transitions to vacant π4 * -MO states of the tta ligands.