Listar QFA_Articles por fecha de publicación
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Towards understanding of magnetic interactions within a series of tetrathiafulvalene- conjugated- verdazyl diradical cation system: a density funtional theory study
Royal Society of Chemistry (2008)The intramolecular magnetic exchange coupling constants (J) for a series of tetrathiafulvalene (TTF) and verdazyl diradical cations connected by a range of p conjugated linkers have been investigated by means of methodology ... -
Magnetic interactions in thiazyl-based magnets: The role of the charge and spin densities
International Union of Crystallography (2008)The crystal structure of the organic radical p-O2NC6F4CNSSN was determined at 20 K through a single-crystal neutron-diffraction experiment. It crystallises in the tetragonal space group P41212, unchanged from a previous ... -
Tuning the tunnel coupling of quantum dot molecules with longitudinal magnetic fields
American Institute of Physics (2008)We show that the energy splitting between the bonding and antibonding molecular states of holes in vertically stacked quantum dots can be tuned using longitudinal magnetic fields. With increasing field, the energy splitting ... -
Fast determination of toxic diethylene glycol in toothpaste by ultra-performance liquid chromatography–time of flight mass spectrometry
Springer Verlag (2008)A rapid method for determining diethylene glycol (DEG) in toothpaste based on the use of ultraperformance liquid chromatography (UPLC) coupled to time-of-flight mass spectrometry (TOF-MS) has been developed. The method ... -
An electron localization function and catastrophe theory analysis on the molecular mechanism of gas-phase identity SN2 reactions
Springer Verlag (2008)A set of four reactions, XCH3+X− (X=F, Cl, Br) and ClSiH3+Cl−, is investigated by means of the joint use of the electron localization function (ELF) and catastrophe theory (CT) analysis in order to obtain newinsights ... -
Characteristic molecular properties of one-electron double quantum rings under magnetic fields
Institute of Physics (2008)The molecular states of conduction electrons in laterally coupled quantum rings are investigated theoretically. The states are shown to have a distinct magnetic field dependence, which gives rise to periodic fluctuations ... -
Photoluminescence spectroscopy of trions in quantum dots: A theoretical description
American Physical Society (2008)We present a full configuration-interaction study of the spontaneous recombination of neutral and singly charged excitons trions in semiconductor quantum dots from weak- to strong-coupling regimes. We find that the ... -
Determination of PBDEs in human breast adipose tissues by gas chromatography coupled to triple quadrupole mass spectrometry
Springer Verlag (2008)The potential of gas chromatography / tandem mass spectrometry with triple quadrupole analyzer for determination of 12 polybrominated diphenyl ethers in human breast tissues has been investigated. After extraction with ... -
Isospin phases of vertically coupled double quantum rings under the influence
American Physical Society (2008)Vertically coupled double quantum rings submitted to a perpendicular magnetic field B are addressed within the local spin-density-functional theory. We describe the structure of quantum ring molecules containing up to 40 ... -
Pesticide residues and transformation products in groundwater from a Spanish agricultural region on the Mediterranean Coast
Taylor & Francis (2008)An overview is given on the presence and changes over time of pesticide residues in groundwater from the Valencia region, one of the most important citrus cultivation sites of southern Europe. A multiresidue LC-MS/MS ... -
Dielectric control of spin in semiconductor spherical quantum dots
American Institute of Physics (2008)The ground state electronic configuration of semiconductor spherical quantum dots populated with different numbers of excess electrons, for different radii and dielectric constants of the embedding medium is calculated ... -
Delocalized image surface states in defects free SiO2 hollow nanospheres
American Institute of Physics (2008)Delocalized image surface states in free-standing hollow silica nanospheres populated with one or two electrons or an exciton are theoretically predicted for a wide range of internal radii and shell thicknesses. The ... -
Coupling of the Guanosine Glycosidic Bond Conformation and the Ribonucleotide Cleavage Reaction: Implications for Barnase Catalysis
Wiley-Blackwell (2008)To examine the possible relationship of guanine-dependent GpA conformations with ribonucleotide cleavage, two potential of mean force (PMF) calculations were performed in aqueous solution. In the first calculation, the ... -
QM/MM simulations for methyl transfer in solution and catalysed by COMT: ensemble-averaging of kinetic isotope effects
Royal Society of Chemistry (2008)Sampling of structures from QM/MM molecular dynamics reveals distinct families of reactant-state conformers and yields kinetic isotope effects for reactions in enzyme active sites and in solution, averaged over thermal ... -
Predicting an improvement of secondary catalytic activity of promiscuos isochorismate pyruvate pyase by computational design
American Chemical Society (2008)Improvement of the secondary catalytic activity of promiscuous enzymes can be guided by computational protein engineering. This methodology has been applied to isochorismate pyruvate lyase (IPL) that catalyzes isochorismate ... -
Using Grote-Hynes theory to quantify dynamical effects on the reaction rate of enzymatic processes. The case of Methyltransferases
American Chemical Society (2008)Dynamical effects have recently received much attention in the context of the theoretical investigation of enzymatic catalysis. In this paper we use a combination of Grote−Hynes theory with quantum mechanical/molecular ... -
Theoretical site-directed mutagenesis. The Asp168Ala mutant of L-Lactate Dehydrogenase
Royal Society (Gran Bretanya) (2008)The reduction of pyruvate to lactate catalyzed by the L-Lactate dehydrogenase has been studied in this paper by means of hybrid Quantum Mechanical / Molecular Mechanical simulations. A very flexible molecular model ... -
Dynamic effects on reaction rates in a Michael Addition catalyzed by Chalcone Isomerase. Beyond the frozen environment approach
American Chemical Society (2008)We present a detailed microscopic study of the dynamics of the Michael addition reaction leading from 6′-deoxychalcone to the corresponding flavanone. The reaction dynamics are analyzed for both the uncatalyzed reaction ... -
Computational design of biological catalysts
Royal Society of Chemistry (2008)The purpose of this tutorial review is to illustrate the way to design new and powerful catalysts. The first possibility to get a biological catalyst for a given chemical process is to use existing enzymes that catalyze ... -
A Quantum Mechanics / Molecular Mechanics Study of the Protein-Ligand Interaction of two potent inhibitors of human O-GlcNAcase: PUGNAc and NAG-thiazoline
American Chemical Society (2008)O-glycoprotein 2-acetamino-2-deoxy-β-D-glucopyranosidase (O-GlcNAcase) hydrolyzes 2-acetamido-2-deoxy-β-D-glucopyranose (O-GlcNAc) residues of serine/threonine residues of modified proteins. O-GlcNAc is present in many ...