The complete detailed reaction mechanism for the oxidative dehydrogenation of ethane over Fe-ZSM-5 zeolite has been systematically investigated by means of the ONIOM(MP2/6-31G(d,p):UFF)//ONIOM(B3LYP/6-31G(d,p):UFF) scheme. Two types of reaction mechanisms for the oxidative dehydrogenation of ethane have been suggested: stepwise and concerted. The concerted mechanism, the concurrent abstraction ...

In a series of systematic studies, we have investigated the molecular motion in crystals of the glycine polymorphs and determined their thermodynamic functions from an analysis of multitemperature atomic displacement parameters (ADPs) combined with ONIOM calculation on 15-molecule clusters. The studies are aimed at providing insight into the factors governing the relative stabilities of the α-,...

We have designed and theoretically studied three different pairs of green fluorescent protein chromophores and their different homologue-based diradicals coupled with imino nitroxides. To begin with, the geometries of all these diradicals have been optimized at high spin (HS) state in the gas phase, in a water medium and in a blood plasma medium. The process of calculations is straightforward a...

In this study, functionalized β-cyclodextrin (β-CD) by aldehyde group was investigated as an oxidase enzyme mimic for the amino phenol oxidation. All calculations were performed by GAUSSIAN 09 package using two layers ONIOM method at the ONIOM (MPW1PW91/6-311++G(d,p)/UFF) level. In the first step, H2O2 is encapsulated in the hydrophobic cavity. In the second step, H2<...

The oxidative half-reaction of oxygen atom transfer from nitrate to an Mo(IV) complex has been investigated at various levels of theory. Two models have been used to simulate the enzyme active site. In the second, more advanced model, additional amino acid residues capable of significantly affecting the catalytic efficiency of the enzyme were included. B3LYP/6-31+G*, ONIOM, and orbital-free emb...

The 1,3-dipolar cycloaddition between glycine-derived azlactones with maleimides is efficiently catalyzed by the dimeric chiral complex [(S a)-Binap·AuTFA]2. The alanine-derived oxazolone only reacts with tert-butyl acrylate giving anomalous regiochemistry, which is explained and supported by Natural Resonance Theory and Nucleus Independent Chemical Shifts calculations. The origin of the high e...