Author(s): Toubin C; Yeung DY; English AM; Peslherbe GH;

The degradation of S-nitrosothiols (RSNOs) to release NO is believed to be catalyzed by CuI ions, but the mechanism remains unclear. Kinetic experiments have shown that decomposition rates vary significantly with the chemical nature of the RSNO considered. On the basis of first-principles calculations, the catalytic role of CuI ion is investigated for the ...

Article GUID: 12475301

Author(s): Hernández de la Peña L; Peslherbe GH;

Nonequilibrium simulation methods and rigid-body path-integral techniques are combined to estimate the relevance of protonic quantum effects in the free energy of ion-water clusters. The Crooks' fluctuation relation is used to quantitatively characterize the impact of quantum effects on the dissociation free energy of the paradigm I(-)(H(2)O)(5). By u ...

Article GUID: 20377185

Author(s): Nguyen TN; Timerghazin QK; Vach H; Peslherbe GH;

Molecular electronic excitation in (O(2))(n) clusters induced by mechanical collisions via the "chemistry with a hammer" is investigated by a combination of molecular dynamics simulations and quantum chemistry calculations. Complete active space self-consistent field augmented with triple-zeta polarizable basis set quantum chemistry calculations of a comp ...

Article GUID: 21322678

Author(s): Varadwaj PR; Varadwaj A; Peslherbe GH; Marques HM;

Density functional theory calculations, together with quantum theory of atoms in molecules (QTAIM) analyses, have been performed to investigate 18-azacrown-6 complexes of the high-spin late first transition series divalent metal ions in the gas phase and, in some cases, in aqueous solution simulated by a polarizable continuum model. Six intramolecular H-H ...

Article GUID: 21961695

Author(s): Mak CC; Timerghazin QK; Peslherbe GH;

Upon photoexcitation of iodide-water clusters, I(-)(H(2)O)(n), an electron is transferred from iodide to a diffuse cluster-supported, dipole-bound orbital. Recent femtosecond photoelectron spectroscopy experiments have shown that, for photoexcited I(-)(H(2)O)(n) (n= 5), complex excited-state dynamics ultimately result in the stabilization of the transferr ...

Article GUID: 22466252

Author(s): Shadrina MS; English AM; Peslherbe GH;

The diffusion of small gases to special binding sites within polypeptide matrices pivotally defines the biochemical specificity and reactivity of proteins. We investigate here explicit O(2) diffusion in adult human hemoglobin (HbA) as a case study employing the recently developed temperature-controlled locally enhanced sampling (TLES) method and vary the ...

Article GUID: 22690872

Author(s): Varadwaj PR; Varadwaj A; Peslherbe GH;

The proton accepting and donating abilities of cyclopropenylidene (c-C(3)H(2)) on its complexation with hydrogen halides H-X (X = F, Cl, Br) are analyzed using density-functional theory with three functionals (PBE0, B3LYP, and B3LYP-D) and benchmarked against second-order Møller-Plesset (MP2) theory. Standard signatures including, inter alia, dipole momen ...

Article GUID: 22696309

Author(s): Zhang L; Muchall HM; Peslherbe GH;

The ground-state equilibrium geometries, electronic structures and vertical excitation energies of methyl- and methoxyl-substituted phenol radical cations and phenoxyl radicals have been investigated using time-dependent density-functional theory (namely TD-B3LYP) and complete-active-space second-order perturbation theory (CASPT2). The "anomalous" large r ...

Article GUID: 23216064

Author(s): Jahangiri S; Mercer SM; Jessop PG; Peslherbe GH;

The solvation behavior of alkyl diammonium chlorides of varying alkyl chain length and the molecular details of their effect on the salting-out of organic molecules in aqueous phase have been investigated by classical molecular dynamics simulations. More specifically, systems containing water, tetrahydrofuran (THF), and their mixtures with a,?-alkyl diamm ...

Article GUID: 23789929

Author(s): Mak CC; Timerghazin QK; Peslherbe GH;

Photoexcitation of iodide-acetonitrile clusters, I(-)(CH3CN)n, to the charge-transfer-to-solvent (CTTS) state and subsequent cluster relaxation could result in the possible formation of cluster analogues of the bulk solvated electron. In this work, the relaxation process of the CTTS excited iodide-acetonitrile binary complex, [I(-)(CH3CN)]*, is investigat ...

Article GUID: 23819756

Author(s): Mak CC; Peslherbe GH;

Upon photoexcitation of iodide-methanol clusters, I(-)(CH3OH)n, to a charge-transfer-to-solvent (CTTS) excited state, extensive relaxation was found to occur, accompanied by a convoluted modulation of the stability of the excited electron, which ultimately decreases substantially. In order to develop a molecular-level understanding of the relaxation proce ...

Article GUID: 24922343