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Vincent K. Shen, Mark J. Pond, William P. Krekelberg, Jeffrey R. Errington, Thomas M. Truskett
We report molecular dynamics simulation results for two-component fluid mixtures of Gaussian-core particles, focusing on how tracer diffusivities and static pair correlations depend on temperature, particle concentration, and composition. At low particle
Russell D. Johnson III, Karl K. Irikura, Raghu N. Kacker, Ruediger Kessel
To predict the vibrational spectra of molecules, ab initio calculations are often used to compute harmonic frequencies, which are usually scaled by empirical factors as an approximate correction for errors in the force constants and for anharmonic effects
F Case, Anne M. Chaka, J Moore, Raymond D. Mountain, J Olson, Richard B. Ross, Martin Schiller, Vincent K. Shen, Eric A. Stahlberg
The fifth industrial fluid properties simulation challenge was held in 2008. In it the contestants were challenged to predict specific, industrially relevant, properties of fluid systems, namely the 1-octanol /water partition coefficient and the infinite
Karl K. Irikura, Russell D. Johnson III, Raghu N. Kacker, Ruediger Kessel
Vibrational zero-point energies (ZPEs) determined from ab initio calculations are often scaled by empirical factors. An empirical scaling factor partially compensates for the effects arising from vibrational anharmonicity and incomplete treatment of
Composite ab initio and density functional theory (DFT) methods were used to explore internal hydrogen-atom transfers in a variety of primary, secondary, and tertiary alkyl and functionalized radicals with implications for combustion environments. The
Methyl esters are commonly used as surrogates for complex biofuel chemistry; this utility necessitates development of combustion mechanisms for these species. A pathway accounting for early CO2 production in the combustion of methyl esters, using methyl
DNA has become a major target for clinical laboratory testing over the past 5 years, and RNA testing is emerging for infectious disease and gene expression (1). To normalize laboratory results across different technology platforms as well as between
Proton transfer in bacteriorhodopsin from the cytoplasm to the extracellular side is initiated from protonated asp96 in the cytoplasmic region towards the deprotonated Schiff base. This occurs in the transition from the photocycle late M state to the N
Y. S. Lee, S. E. Worthington, Morris Krauss, B R. Brooks
The reaction path for the rearrangement of chorismate to prephenate has been determined in a QM/MM study including the entire protein environment while treating the reaction with ab initio quantum chemistry. In addition to the reactant, chorismate, the
The detection limit is an important figure of merit for evaluating instrumentation and analytical methods. While the detection limit for techniques using linear calibration functions has been studied extensively, this fundamental metric has rarely been
The structure of the active site of human glyoxalase I and the reaction mechanism of the enzyme-catalyzed conversion of the thiohemiacetal, formed from methylglyoxal and glutathione, to S-D-lactoylglutathione has been investigated by ab initio quantum
This research exploits two recent developments to obtain a fundamental understanding of the metalloenzyme active site using the bi-metallic enzyme phosphotriesterase as an example of this class. First, is the theoretical prediction that the structure and