As an example from amore extensive investigation, the binding analysis of the mixture PtSnM (M = undetermined mole number) is described. A phase becomes stable when a lattice-like correlation of the valence electrons (with cell b) and a lattice-like correlation of the peripheral core electrons of Pt (cell e) are in an energetically favourable commensurability to the crystal cell a and to one an...

An ab initio computational study on a series of sulfoxides is reported. The SO bond dissociation energy (BDE) of sulfoxides in which the sulfur atom is included in a formally aromatic ring (e.g., thiophene sulfoxide) is found to be decreased by as much as 25 kcal/mol, compared to DMSO. A complementary effect is observed for sulfoxides in which the sulfur is included in a formally antiaromatic r...

Gaussian-2 and QCI theory with basis sets up to 6-311+G(3df,2p) have been employed to obtain information about the carbenes (methylenes) CH2, CHBr, CHCl, CHF, CHI, CBr2, CBrCl, CBrF, CBrI, CCl2, CClF, CClI, CF2, and CI2. Geometries and vibrational frequencies for the singlet and triplet states, and the singlet-triplet splittings, have been characterized and are discussed in the context of the e...

Quantum chemical composite methods G3MP2B3, G3B3, G4MP2 and G4 have been used to calculate enthalpies of formation and gas phase basicities of the title compounds. Comparison of the results with the available experimental heats of formation values reveals correct agreement (to within ≈ 2 kJ/mol) with G3B3 and G4 methods. Systematic errors on the heats of formation of these aromatic molecules ar...

It has recently been pointed out that current density functionals are inaccurate for computing stereoelectronic effects and energy differences of isomerization reactions and isodesmic reactions involving alkanes; this has been interpreted as an incorrect prediction of medium-range correlation energies. This letter shows that the recently published M05-2X functional has good accuracy for all thr...

Hydrogen is considered as a unique choice for future world’s resources. The important parameter in the process of hydrogen production is the value of reduction potential for the used catalyst, in direct contact with consumed energy in process. The application of computational methods to design and modify molecular catalysts is highly regarded. This study sought to explore Density Functional...

X-ray scattering and various optical techniques are utilized to study the aggregation process and chromonic liquid crystal phase of the anionic monoazo dye Sunset Yellow FCF. The x-ray results demonstrate that aggregation involves pi-pi stacking of the molecules into columns, with the columns undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye ...