A systematic study on bis(dicyclooctatetraenyl)diuranium (U 2 COT 4 ) has been performed using relativistic density functional theory. The molecule was calculated in four different electronic configurations and the two symmetries C 2 and D 2h . First we considered the high-spin quintuplet ( 5 A) state, and from this state we built the broken-symmetry configuration following Noodleman's approach. Also, the triplet state was considered as a formal interaction of both uranocene fragments in triplet and singlet states simultaneously, and finally the low-spin singlet configuration was calculated. For both symmetries the ground state of the complex was the quintuplet, and on the basis of the broken-symmetry approach a significant ferromagnetic coupling between both metals was found. Time-dependent density functional theory (TDDFT) was used to calculate the excitation energies with the GGA SAOP functional. The obtained electronic transitions are in good correlation with reported experimental values, which are found between 600 and 720 nm: 633, 658, 664, 673, 685, and 717 nm.

Phosphofructokinases catalyze the ATP-dependent phosphorylation of fructose-6-phosphate and they are highly regulated.

The rarely recognized electron donating ability of the benzophenone triplet excited state provides an unusual route for the photochemical synthesis of gold nanoparticles.

A systematic study of a series of An(COT)(2) compounds, where An = Th, Pa, U, and COT represents cyclooctatetraene, has been performed using relativistic density functional theory. The ZORA Hamiltonian was applied for the inclusion of relativistic effects, taking into account all of the electrons for the optimization and explicitly including spin-orbit coupling effects. Time-dependent density functional theory (TDDFT) was used to calculate the excitation energies with the GGA SAOP functional, and the electronic transitions were analyzed using double group irreducible representations. The calculated excitation energies are in perfect correlation with the increment of the ring delocalization as it increases along the actinide series. These results are sufficient to ensure that, for these complexes, the increment in delocalization, as indicated by ELF bifurcation and NICS analysis, leads to a shift in the maximum wavelength of absorption in the visible region. Also, delocalization in the COT ring increases along the actinide series, so the systems become more aromatic because of a modulation induced by the actinides.

The high interest in lanthanide chemistry, and particularly in their luminescence, has been encouraged by the need of understanding the lanthanide chemical coordination and how the design of new luminescent materials can be affected by this. This work is focused on the understanding of the electronic structure, bonding nature, and optical properties of a set of lanthanide hexaaza macrocyclic complexes, which can lead to potential optical applications. Here we found that the DFT ground state of the open-shell complexes are mainly characterized by the manifold of low lying f states, having small HOMO-LUMO energy gaps. The results obtained from the wave function theory calculations (SO-RASSI) put on evidence the multiconfigurational character of their ground state and it is observed that the large spin-orbit coupling and the weak crystal field produce a strong mix of the ground and the excited states. The electron localization function (ELF) and the energy decomposition analysis (EDA) support the idea of a dative interaction between the macrocyclic ligand and the lanthanide center for all the studied systems; noting that, this interaction has a covalent character, where the d-orbital participation is evidenced from NBO analysis, leaving the f shell completely noninteracting in the chemical bonding. From the optical part we observed in all cases the characteristic intraligand (IL) (π-π*) and ligand to metal charge-transfer (LMCT) bands that are present in the ultraviolet and visible regions, and for the open-shell complexes we found the inherent f-f electronic transitions on the visible and near-infrared region.