A ferramenta de Gassman-Fentiman da demanda crescente de elétrons foi usada para identificar íons carbênios e íons carbônios. Contudo, devido ao seu entendimento ambíguo, ela foi pivô de uma disputa histórica. Nós aplicamos a metodologia da Teoria Quântica de Átomos em Moléculas QTAIM para caracterizar íons carbênios e íons carbônios de uma forma mais eficaz e mais fácil. Essa metodologia pode ...

A new, more flexible definition of fuzzy Voronoi cells is proposed as a computationally efficient alternative to Bader's Quantum Theory of Atoms in Molecules (QTAIM) partitioning of the physical space for large-scale routine calculations. The new fuzzy scheme provides atomic charges, delocalization indices, and molecular energy components very close to those obtained using QTAIM. The method is ...

The topological diversity of sets of isomers of water clusters (W = H2O)n, 7 ≤ n ≤ 10, is analyzed employing the scalar fields of total electronic charge density ρ(r) and the molecular electrostatic potential (MESP). The features uncovered by the MESP are shown to be complementary to those revealed by the theory of atoms in molecules (QTAIM) analysis. The MESP is known to exhibit the electron l...

Tetrel bond is analysed for a series of ZF4 (Z = C, Si, Ge) complexes with one and two NH3 or AsH3 ligands. The MP2/aug-cc-pVTZ calculations were performed and supported by results of the Quantum Theory of “Atoms in Molecules” (QTAIM) and the Natural Bond Orbitals (NBO) approaches. The Z-tetrel atoms of complexes analysed interact through their σ-holes with nitrogen or arsenic Lewis base centre...

A assistência da deslocalização de elétrons sigma ou assistência anquimérica dos elétrons sigma explica grandes diferenças de velocidade na solvólise de 2-exoe 2-endo-norbornilp-bromobenzenosulfonatos. Este estudo foi anteriormente analisado pela teoria dos orbitais moleculares em fase gás. Ao revisitar este antigo problema a partir da teoria quântica de átomos em moléculas (QTAIM), novas infor...

A new approach for computing the atom-in-molecule [quantum theory of atoms in molecule (QTAIM)] energies in Kohn-Sham density-functional theory is presented and tested by computing QTAIM energies for a set of representative molecules. In the new approach, the contribution for the correlation-kinetic energy (T(c)) is computed using the density-functional theory virial relation. Based on our calc...

The bonding in monomeric and dimeric molecular compounds of Cr, Mo, W and U is explored using the Quantum Theory of Atoms-in-Molecules (QTAIM). The metal-ligand and metal-metal bond critical point properties ρb, ∇(2)ρb and Hb, and also the bond delocalisation indices δ(A, B), are correlated with the data from previous Ziegler-Rauk energy decomposition studies of the same systems. For M2X6 (M = ...

dft and qtaim computations have been performed on numbers of pure nitrogen cluster speciesi.e. nn (n = 4, 6) for investigating the structure and bonding. this study is critical since thesemolecules have been nominated as the good synthetic targets of high energy materials (hem).0nthe other hand the decomposition mechanism is closely depends on the bonding pattern. thislatter concept was searche...

The Structural theory of chemistry introduces chemical/molecular structure as a combination of relative arrangement and bonding patterns of atoms in a molecule. Nowadays, the structure of atoms in molecules is derived from the topological analysis of the quantum theory of atoms in molecules (QTAIM). In this context, a molecular structure is varied by large geometrical variations and concomitant...

The recent synthesis of a crystalline compound containing Ti bonded to cyclopentadienyl and a substituted dienyl fragment prompted the question of whether Ti-C contacts that were found to be shorter than other such bonded contacts in the same molecule should be considered as short nonbonded contacts or "nonclassical metal-to-saturated-carbon atom interactions", fitting the description of agosti...