Calcium is the 5th most abundant element on earth, and is found in numerous biological tissues, proteins, materials, and increasingly in catalysts. However, due to a number of unfavourable nuclear properties, such as a low magnetogyric ratio, very low natural abundance, and its nuclear electric quadrupole moment, development of solid-state (43)Ca NMR has been constrained relative to similar nuc...

We performed predictive hybrid-DFT computations for PbTiO3, BaTiO3, SrTiO3, PbZrO3 and SrZrO3 (001) surfaces, as well their BaTiO3/SrTiO3, PbTiO3/SrTiO3 PbZrO3/SrZrO3 heterostructures. According to our BO2 AO-terminated ABO3 solid in most cases, the upper layer ions relax inwards, whereas second shift upwards. Our computed surface rumpling s BO2-terminated perovskite surfaces almost always is p...

We propose and consolidate a definition of the discrete fractional Fourier transform that generalizes the discrete Fourier transform (DFT) in the same sense that the continuous fractional Fourier transform generalizes the continuous ordinary Fourier transform. This definition is based on a particular set of eigenvectors of the DFT matrix, which constitutes the discrete counterpart of the set of...

The present work is related to predicting the pKa values of organosulfur compounds through density functional theory (DFT). In this study, 22 were considered calculate theoretical values. main emphasis was given on substitution different groups sulfur atom. computations performed in presence dimethyl sulfoxide (DMSO) as solvent. Experimentally, order increase acidity is; sulfides < sulfoxide...

Multicomponent reactions are attracting strong interest as they contribute to the development of more efficient synthetic chemistry. Understanding their mechanism is thus an important issue optimize operation. However, it also a challenging task owing complexity succession molecular events involved. Computational methods have recently proven be utmost help decipher some these processes, and int...

Ten novel hydrogen-bonding catalysts based on open-chain P(V)-amides of BINOL and chinchona alkaloids as well as three catalysts based on rigid cis-P(V)-cyclodiphosphazane amides of N (1),N (1)-dimethylcyclohexane-1,2-diamine have been developed. Employed in the asymmetric Michael addition of 2-hydroxynaphthoquinone to β-nitrostyrene, the open-chain 9-epi-aminochinchona-based phosphorus amides ...

In quantum chemical computations the combination of Hartree-Fock or a density functional theory (DFT) approximation with relatively small atomic orbital basis sets of double-zeta quality is still widely used, for example, in the popular B3LYP/6-31G* approach. In this Review, we critically analyze the two main sources of error in such computations, that is, the basis set superposition error on t...