We study chemical aging in "Cooee bitumen" using molecular dynamic simulations. This model bitumen is composed of four realistic molecule types: saturated hydrocarbon, resinous oil, resin, and asphaltene. The aging reaction is modelled by the chemical reaction: "2 resins → 1 asphaltene." Molecular dynamic simulations of four bitumen compositions, obtained by a repeated application of the aging ...

An attempt has been made to study the reaction between a uranium atom and a nitrogen molecule theoretically using multiconfigurational wave functions. The C2v part of the reaction surface has been computed for several electronic states of various spin mulltiplicities. The system proceeds from a neutral uranium atom in its (5f)3(6d)(7s)2, 5L ground state to the linear molecule NUN, which has a 1...

We present a theoretical investigation of the chemical reaction SrF + SrF → products, focusing on reactions at ultralow temperatures. We find that bond swapping SrF + SrF → Sr2 + F2 is energetically forbidden at these temperatures. Rather, the only energetically allowed reaction is SrF + SrF → SrF2 + Sr, and even then only singlet states of the SrF2 trimer can form. A calculation along a reduce...

this study concerns about quantum chemical modeling behavior of 02 on cr (100)surface by using density functional theory (dft) by lanl2dz and 6 — 31g* basissets, we presented the results of our first principles electronic structure calculationson the 02 molecules and their interface with cr (100) surface. the chromium metalhas the body-centered cubic structure, and chromium cluster has five cr ...

In this work we use classical methods to develop an accurate model able describe the interactions between molecule of water and hematite surface. We study variation interaction energy surface regarding some geometrical aspects such as proximity different parts surface, molecule-surface distance, orientation molecule. obtain profiles compare them with results obtained using DFT. polarizable non-...

aminocarboxylic acids, such as 2-aminobenzoic acid, react easily with [ir(cod)(pme3)3]cl, (cod=1,5-cyclooctadiene), in thf to produce hydridoaminocarboxylato iridium(iii) complexes in high yields. these octahedral complexes are formed via oxidative addition reaction of the o-h bond of the carboxylic group with the central metal. the starting iridium(i) complex losses the cod molecule, the chlor...

An explicit application of isodesmic reaction (a proton exchange between the studied and similar in structure reference molecule), where the free energy change of the protonation reaction in water was obtained using the free energies in solution from a single continuum model, was used to predict stepwise protonation constants of nitrilotriacetic acid. Calculations were performed at the RB3LYP/6...

Single-molecule detection can reveal time trajectories and reaction pathways of individual intermediates/transition states in chemical reactions and biological processes, which is of fundamental importance to elucidate their intrinsic mechanisms. We present a reliable, label-free single-molecule approach that allows us to directly explore the dynamic process of basic chemical reactions at the s...

the synthesis of 3-amino-1-nitroguanidine (3-anq) and 5-hydrazino tetrazole (5-ht) derivatives as new energetic materials are described. reaction of 3-anq with triethyl orthoformate leads to the formation of 3-nitramino triazole while no reaction was observed whit 5-ht. addition of nan3 to a mixture of 3-anq and triethyl orthoformate, afforded 1-nitroguanidyl tetrazole in excellent yield. on th...