The nonstatistical dissociation of acetone radical cation has been studied by ab initio direct classical trajectory calculations at the MP2/6-31G(d) level of theory. A bond additivity correction has been used to improve the MP2 potential energy surface (BAC-MP2). The energy dependence of the branching ratio, dissociation kinetics, and translational energy distribution for the two types of methy...

EXPERIMENTAL AND THEORETICAL STUDIES OF BINDING INTERACTIONSIN DIVALENT TRANSITION METAL CATION-N-DONOR LIGANDCOMPLEXES: STRUCTURES, SEQUENTIAL BOND DISSOCIATION ENERGIES,MECHANISMS AND ENERGETICS OF COLLISION-INDUCED DISSOCIATION

The results from three recent types of experiment investigating the interaction potential between a hydrogen atom and a carbon monoxide molecule are summarized and compared to theoretical predictions based on an ab initio HCO potential energy surface. In the first experiment, energetic hydrogen atoms generated in the photolysis of H2S collisionally excite CO molecules to high rotational levels ...

A comprehensive metadynamics study of the energetics, stability, conformational changes, and mechanism of dissociation of gas phase carbonic acid, H2CO3, yields significant new insight into these reactions. The equilibrium geometries, vibrational frequencies, and conformer energies calculated using the density functional theory are in good agreement with the previous theoretical predictions. At...

Molecular constants have been computed for the ground states 2∏ of 17OH and 1Σ of 107AgH+. The valence-bond method and advanced computational technique were used to perform all-electron ab initio calculation of molecular electronic structures. The basic idea behind the model is to introduce the molecular wave functions in terms of Hartree-Fock many-electron atomic determinants. Full configurati...

Density functional theory calculations based on different representations of the exchange-correlation functional (BLYP, B3LYP, B3PW91, mPW1PW91, B1LYP, BHandHLYP, BHandH, and B3P86) were carried out to predict C–H bond dissociation enthalpies in selected ethers (dimethyl ether, tetrahydrofuran (thf), and 1,4-dioxane), and some related molecules. Comparison with available experimental informatio...

Predissociation dynamics of methylamines (CH(3)NH(2) and CH(3)ND(2)) on the first electronically excited states are studied using the slow-electron velocity imaging method to unravel the multi-dimensional nature of the N-H(D) chemical bond dissociation reaction which occurs via tunnelling. The nearly free internal rotation around the C-N bond axis is found to be strongly coupled to the reaction...

It is important but unclear how protein-ligand system motions affect free energy profiles, create energy barriers, and lead to slow residence time. We computed residence time (RT) and potential of mean force (PMF) of the dissociations of five structure-kinetic relationship (SKRs) series inhibitors of CDK8/CycC using metadynamics and milestoning theory. By using a novel way to represent the reac...

We report threshold electron energy-loss spectra for the fluorohalomethanes CF3X (X=Cl,Br). Measurements were made at incident electron energies of 30 and 100 eV in energy-loss range of 4-14 eV, and at scattering angles of 4 degrees and 15 degrees. Several new electronic transitions are observed which are ascribable to excitation of low-lying states as well as are intrinsically overlapped in th...

The radicals generated by the homolytic cleavage of an X-H bond from the guanine.cytosine (G.C) base pair were studied by using carefully calibrated theoretical methods. The gradient-corrected density functional B3LYP was applied in conjunction with double-zeta plus polarization and diffuse function basis sets. Optimized geometries, energies, and vibrational frequencies were obtained for all of...