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Based on the relationship between average local ionization energy I ̄ (r) and average local electron affinity A ̄ (r) with the electronic Fukui functions, i.e., f−(r) and f+(r), respectively, in this paper, we establish a connection between nuclear and electronic Fukui functions beyond frontier molecular orbitals. As a consequence of this connection, we obtain expressions of average nuclear Fukui functions interpreted as a variation of average nucleophilicity or electrophilicity (weighted by the electronic orbital Fukui functions) with respect to nuclear displacements, which goes beyond the highest occupied molecular orbital/or lowest unoccupied molecular orbital consideration. Furthermore, from this connection and considering the frontier molecular orbital approximation, we derive expressions of nuclear Fukui functions in terms of the atom-condensed electronic Fukui functions, which imply a locality in the chemical reactivity and could be used to study the variation of local nucleophilicity or electrophilicity with respect to nuclear displacements. Finally, this new way to interpret the nuclear Fukui function could be useful in the future to study the chemical reactivity related to molecular vibrations, internal rotations, bond dissociation, chemical reaction along the model of reaction coordinate, and so on. [ABSTRACT FROM AUTHOR]

In our continuous effort to retrieve the Woodward-Hoffmann rules from conceptual density functional theory (DFT), we have examined the last type of pericyclic reactions, i.e., chelotropic reactions. Both the initial hardness response and the dual descriptor have been investigated to predict the allowed and forbidden character for the addition of S[O.sub.2] to butadiene (4n system) and 1,3,5-hexatriene (4n + 2 system). It is shown that with both electronic descriptors, the conrotatory/disrotatory mode for the linear and nonlinear mechanisms are retrieved based on a density-only approach, free from consideration of orbital and (or) wave function symmetry. The dual descriptor moreover reveals that stabilizing interactions are presented only for the linear path, which can be considered as an overall favourable mechanism for a chelotropic reaction. Key words: chelotropic reactions, Woodward-Hoffmann rules, conceptual DFT. Dans le cadre de nos travaux pour recuperer les regles de Woodward-Hoffmann a partir de la theorie de la fonctionnelle de la densite conceptuelle, on a etudie le dernier type de reactions pericycliques, a savoir les reactions cheelotropes. On a etudie tant la reponse initiale de la durete que le descripteur dual pour predire le caractere permis et interdit pour l'addition du S[O.sub.2] sur le butadiene (systeme 4n) et hexa-1,3,5-triene (systeme 4n + 2). Il est demontre que pour les deux descripteurs electroniques, on peut retrouver le mode conrotatoire/disrotatoire pour les meecanismes lineiaires et non lineaires en se basant uniquement sur une approche de densite, sans prendre en consideration l'orbitale et (ou) la symetrie de la fonction d'onde. De plus, le descripteur double ne revele l'existence d'interactions stabilisantes que pour la voie lineaire qui peut etre consideree comme le meecanisme global le plus favorable pour une reaction cheelotrope. Mots-cles: reactions chelotrope, regles de Woodward-Hoffmann, theorie de la fonctionnelle de la densite; conceptuelle (<> conceptuelle). [Traduit par la Redaction], Introduction The Woodward-Hoffmann (WH) rules (1) have played an unprecedented role in predicting/rationalizing the outcome of chemical reactions on the basis of a quantum chemical approach. (2,3) Formulated in the [...]

The formation of neutral copper clusters from dimer to nonamer is studied and rationalized using the experimental data of binding energies and electronic properties. An analytic expression for the binding energy as a function of the cluster size is proposed and used to predict the growth pattern of copper clusters.

A study of the formation of 10 bimolecular complexes from the combination of basic units of the type CHX-XH (X = O, S) is presented. The mechanism for double proton transfer was assessed through the force acting on the system to bring reactants into products.

An investigation of molecular vibrations in hydrogen sulfide and ammonia, and internal rotations in hydrogen peroxide, hydrogen persulfide, hydrogen thioperoxide and ethylene, is presented. It was found that conditions of maximum hardness and minimum polarizability complement the minimum energy criterion for molecular stability.

Five new heteroleptic copper(I) complexes (C1‐5) of the type [Cu(dpa)(P,P)]BF4 based on dipyridylamine (dpa) as N,N ligand and commercial diphosphines as P,P ancillary ligands have been synthesised through a simple methodology with high yields. All complexes were thoroughly characterised by spectroscopic and spectrometric techniques, as well by theoretical calculations. These showed Metal to Ligand Charge Transfer (MLCT) absorptions in the 300–370 nm region, and emission in the 450–520 nm region with quantum yields and lifetimes that depend on the nature of the P,P ligand. The photocatalytic performance of copper(I) complexes C1‐5 was evaluated for their use as photoredox catalysts in ATRA reactions, decarboxylative coupling and an Appel‐type reaction. The use of readily available dpa as N,N ligand constitutes an attractive alternative to the well‐established phenanthroline ligands typically used in photocatalysis. [ABSTRACT FROM AUTHOR]

New 4-amino-3-iminoquinoline derivative ligands (L1–4) were synthesized through an intramolecular exo-dig cyclization of anionic β-diketiminates, containing an N-benzonitrile moiety. The effect of the alkali-metal in this reaction was investigated and an inverse effect between the size of the cation and the cyclization rate was revealed. The effect of the reaction temperature was also studied, in which a direct dependence was observed. Kinetic and theoretical studies were performed in an attempt to clarify the reaction mechanism, obtaining a first-order reaction rate dependence with an activation energy of 20.6 kcal mol−1, with DFT-based calculations supporting the proposed mechanism. In addition, four new aluminium complexes were isolated in high yields (C1–4), which were evaluated as catalysts for the preparation of cyclic carbonates from epoxides and CO2, thus becoming the first examples of the use of β-diketiminate ligands in this catalytic process. The reactions were performed at 80 °C and 1 bar CO2 pressure under solvent-free conditions. We were able to prepare a large variety of cyclic carbonates in excellent selectivities and yields, employing the aluminium complex C3. The L1–4 ligands and C1–4 complexes were characterized using NMR, FT-IR, HRMS, and X-ray diffraction methods. [ABSTRACT FROM AUTHOR]