International Journal of Quantum Chemistry
Copyright © 2014 Wiley Periodicals, Inc., A Wiley Company
Online ISSN: 1097-461X
Associated Title(s): Journal of Computational Chemistry
Recently Published Articles
- Charge distribution in homonuclear bonds: A semiempirical modeling
Giorgio Speranza and Luca Minati
Article first published online: 20 DEC 2013 | DOI: 10.1002/qua.24598
Semiempirical methods are well established tools to simulate complex systems at reasonable low-computational cost. The electronegativity equalization method is here extended to homonuclear bonds, allowing for the development of a new semiempirical model to estimate the charge shared in molecular orbitals of homonuclear molecules.
- Hydration structure of Na+, K+, F−, and Cl− in ambient and supercritical water: A quantum mechanics/molecular mechanics study
Article first published online: 20 DEC 2013 | DOI: 10.1002/qua.24597
Ion solvation in water plays a fundamental role in important biological, geological, and chemical processes. Temperature and pressure affect the microscopic local structure and dynamic properties of the aqueous solutions. Quantum mechanics/molecular mechanics and molecular dynamics simulations provide a fundamental insight into the hydration structure of Na1, K1, F2, and Cl2 at both ambient and supercritical conditions. The coordination number of the ions in supercritical water does not significally decrease compared with that under ambient condition due to local clustering effect.
- Ab initio investigations on the stabilities of AuOnq− (q = 0 to 3; n = 1 to 4) species: Superhalogen behavior of AuOn (n ≥ 2) and their interactions with an alkali metal
Ambrish Kumar Srivastava and Neeraj Misra
Article first published online: 17 DEC 2013 | DOI: 10.1002/qua.24599
AuOn molecular complexes behave as superhalogens for n ≥ 2. Theoretical calculations show that Au can bind with four O atoms and form stable AuOnq− species, where q = 0–3, suggesting that Gold could assume a maximum oxidation state of +7. However, the AuOn superhalogen species interacts with alkali metals to form stable KAuOn complexes, the facto tapping the oxidation state of Au to +5.
- Prediction of the pH-rate profile for dimethyl sulfide oxidation by hydrogen peroxide: The role of elusive H3O2+ Ion
Carlos M. Silva, Poliana L. Silva and Josefredo R. Pliego
Article first published online: 9 DEC 2013 | DOI: 10.1002/qua.24594
Dimethyl sulfide plays an important role in the chemistry of biologically active molecules and the atmosphere, for example, the formation of acid rain and oxidative desulfurization. Theoretical calculations predict the pH dependent kinetics of dimethyl sulfide oxidation by H2O2. In acid medium, the H2O2 species is not protonated. Rather, there is formation of highly reactive H3O+(H2O2)(H2O)2 clusters, yielding a faster kinetics at low pH.
- Electronic properties of the low-lying spin states of dimethylnitrosamine coordinated to Fe(III) heme models: An ab initio study
Ezequiel F. V. Leitão, Elizete Ventura, Otávio L. de Santana and Silmar A. do Monte
Article first published online: 9 DEC 2013 | DOI: 10.1002/qua.24595
The unusual O-coordination mode of nitrosamines to Fe(III) heme models can be clarified through ab initio calculation, with special care to minimize spin contaminations among the competing spin-states. The implications of such spin contaminations at the UHF and UMP2 levels can be evaluated for subsequent geometry optimizations to be performed in the smaller cation.