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[Display omitted] • Low-lying electronic states of the TM(AcAc) 1-3 (TM = Cr, Fe, Co, Ni, Cu) molecules. • Ligand field theory and CASPT2 electronic structure description. • Cu(AcAc) 1 , Ni(AcAc) 2, and Co(AcAc) 3 molecules present as stability peaks. • Quantitative stability description by the ε3 stability ranking function. Transition metal acetylacetonates have a wide range of technological applications, such as modifiers in polymers and polymerization catalysts. Since the electronic structure defines the physical-chemistry properties of these materials and ultimately their selectivity in technological applications, its characterization is of paramount importance. In this work, the general trends on the electronic structure of the transition metal acetylacetonate TM(AcAc) were estimated from qualitative and quantitative approaches. The qualitative picture, based on the ligand field theory, allowed to establish a relation between the d-orbital electron occupancy and the stability of the system, in which the Cu(AcAc) 2 presents a limitrophe case, indicating moderate stability and reactivity. On the quantitative approach, the low-lying electronic states of TM(AcAc) were characterized by highly correlated methods. The thermodynamic and kinetic stabilities of TM(AcAc) n were ranked by using a stability index based on parameters of the wavefunction, namely, the excitation energy, the free energy of atomization, and the HOMO energy, showing a good agreement with the qualitative results. Besides the spectroscopic data provided for TM(AcAc) n , the combined qualitative and quantitative results can guide the choice of a specific TM(AcAc) n in applications that require higher or lower stabilities. [ABSTRACT FROM AUTHOR]

Abstract: A theoretical study of the electronic structure of zinc phthalocyanine (ZnPc) ground state was carried out using ab initio and DFT methods. The DFT and MP2 methods indicated a D 4h structure, while HF predicted a slightly distorted geometry. The DFT infrared spectra with the corrected wave number values presented good agreement with experiment. The solvation influence on the geometrical parameters, atomic charges and HOMO–LUMO energies was estimated with the use of PCM method and DMSO as solvent. The presence of solvent did not alter these parameters, but affected the orbital energies. The aggregation phenomena were studied with ZnPc dimer and trimer structures. The previously unknown ZnPc dimer infrared spectrum was obtained and compared to the one from monomer. The dimer and trimer stabilization energies are indicative that the formation of stacked structures with several ZnPc is a favorable process. [Copyright &y& Elsevier]

Highlights: [•] Low-lying electronic states of the GeB molecule. [•] Spin–orbit states. [•] Molecular constants. [•] Transition probabilities. [ABSTRACT FROM AUTHOR]

Highlights: [•] Accurate structures of aluminum clusters: Al n x (n =1–9, x =0, ±1). [•] Electron affinities and ionization potential. [•] DFT and CCSD(T) electronic calculations. [ABSTRACT FROM AUTHOR]