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E. Kim, Arghavan Safavi-Naini, Kyle McKay, David P. Pappas, P.F Weck, H.R. Sadeghpour, Dustin Hite
The decoherence of trapped-ion quantum bits due to heating of their motional modes is a fundamental science and engineering problem. This heating is attributed to electric- field noise arising from processes on the trap-electrode surfaces. In this work, we
Raymond D. Mountain, Harold Hatch, Vincent K. Shen
The self-assembly of patchy trimer particles with one attractive bead and two repulsive beads is investigated with nonequilibrium molecular dynamics simulations in the presence of a velocity gradient, as would be produced by the application of a shear
We review values of the temperature jump coefficient zeta_T determined from measurements of the acoustic resonance frequencies f_acoust of helium-filled and argon-filled, metal-walled, quasi- spherical cavities near ambient temperature. We combine these
We investigate the role of the intrinsic backbone chain stiffness on the morphology behavior of bottle-brush diblock copolymers by using molecular dynamics simulations of a bead-spring coarse- grained model. We focus on bottle-brush having blocks of the
We investigate the influence of counter-ion valency on the flexibility of highly charged flexible polymer chains by molecular dynamics simulations that include both salt and an explicit solvent. As observed experimentally, we find that divalent counter
Cedric J. Powell, Giorgia Olivieri, Krista Parry, Douglas Tobias, Matthew Brown
Over the past decade, energy-dependent X-ray photoelectron spectroscopy (XPS) has emerged as a powerful analytical probe of the ion spatial distributions at the vapor (vacuum)-aqueous electrolyte interface. These experiments are often paired with
In this work, we have compiled enthalpies of formation for nine hydrogen-oxygen species (HxOy) and selected values for use. The compilation consists of values derived from experimental measurements, quantum chemical calculations, and evaluations. This work
Daniel Siderius, Vincent K. Shen, Raymond D. Mountain, Richard B. Ross, David B. Aeschliman, Riaz Ahmad, John K. Brennan, Myles L. Brostrom, Kevin A. Frankel, Jonathan D. Moore, Joshua D. Moore, Derrick M. Poirier, Matthias Thommes, Nathan E. Schultz, Kenneth D. Smith
The primary goal of the eighth industrial fluid properties simulation challenge was to test the ability of molecular simulation methods to predict the adsorption of organic adsorbates in activated carbon materials. The challenge focused, in particular, on
Daniel Siderius, Vincent K. Shen, Raymond D. Mountain, Nathan E. Schultz, Riaz Ahmad, John K. Brennan, Kevin A. Frankel, Jonathan D. Moore, Richard B. Ross, Matthias Thommes, Kenneth D. Smith
The goal of the eighth industrial fluid properties simulation challenge was to test the ability of molecular simulation methods to predict the adsorption of organic adsorbates in activated carbon materials. In particular, the eighth challenge focused on
In this article, recent work on calculating high-quality enthalpies of formation for polycyclic aromatic hydrocarbons (PAHs) based on both density functional theory (DFT) and Gaussian-3 (G3) model chemistry methods is discussed. It is shown that through
In this article, the first principles prediction of enthalpies of formation is demonstrated for 669 polycyclic aromatic hydrocarbon (PAH) compounds and a number of related functionalized molecules. It is shown that by extrapolating density functional
Yauheni Paulechka, Vladimir Diky, Andrei F. Kazakov, Kenneth G. Kroenlein, Michael D. Frenkel
COSMO-SAC model was re-parameterized using the critically evaluated data generated by the NIST ThermoData Engine for vapor-liquid equilibria, excess enthalpies for binary mixtures, and activity coefficients of components of binary mixtures. The calculated
Jay H. Hendricks, Jacob E. Ricker, Jack A. Stone Jr., Patrick F. Egan, Gregory E. Scace, Gregory F. Strouse, Douglas A. Olson, Donavon Gerty
The future of pressure and vacuum measurement will rely on lasers and Fabry-Perot optical cavities, and will be based on fundamental physics of light interacting with a gas. Light interacts at the quantum level with matter such that light travels at a
Jay H. Hendricks, Jacob E. Ricker, Patrick F. Egan, Gregory F. Strouse
Based on highly accurate optical interferometry and fundamental quantum calculations, researchers at the National Institute of Standards and Technology (NIST) in the US are developing an improved definition of the SI unit for pressure that will consign the
RATIONALE: N-Alkylation of sulfonylbenzamides was reported recently to cause a dramatic and surprising change in electron ionization mass spectrometry (EIMS), leading to a closed-shell base peak. Only an incomplete, speculative mechanism was available at
Ryan C. Nieuwendaal, Chad R. Snyder, Dean M. DeLongchamp
We report on details of molecular packing in high molar mass poly(3-hexylthiophene) (P3HT) by solid-state 13C {1H} cross-polarization magic angle spinning (CPMAS) NMR measurements. The degree of polymer order was estimated for two films of varied drying
William P. Krekelberg, Vincent K. Shen, Daniel W. Siderius, Thomas M. Truskett, Jeffrey R. Errington
We investigate the structural and diffusive dynamics properties of a model fluid in highly-absorptive cylindrical pores. At subcritical temperatures, self diffusion displays three distinct regimes as a function of average pore density ρ: 1) a decrease in
Hong Lin, Keith A. Gillis, XiaoJuan Feng, Michael R. Moldover, J.P. Sun, J.T. Zhang, Y.Y. Duan
We report improvements to our previous [Zhang et al., Intl. J. Thermophysics, 32, 1297 (2011)] determination of the Boltzmann constant kB using a single 80 mm-long cylindrical cavity. In this work, the shape of the gas-filled resonant cavity is closer to
Molecular dynamics simulations of aqueous acetonitrile confined in a planar silica slit are presented. It is found, in agreement with experimental observations, that a thin layer of water that excludes acetonitrile is in contact with the hydrophillic
Edwin J. Heilweil, Ryan Compton, Helen K. Gerardi, Daniel Weidinger, Douglas J. Brown, Walter J. Dressick, Jeffrey C. Owrutsky
The RuII cyclometalated dye complex, cis-Ru(bpy)2(N3)2 (where bpy = 2,2-bipyridine), along with two more familiar analogs with pseudohalide (PS) ligands, cis-Ru(bpy)2(NCS)2 and cis-Ru(bpy)2(CN)2, were investigated in solution with static and transient
Yauheni Paulechka, Kenneth G. Kroenlein, Andrei F. Kazakov, Michael D. Frenkel
A systematic, formal approach to optimization of force filed parameters for molecular simulations is presented. The procedure is based on response surface mapping methodology that allows simultaneous parameter optimization against multiple property targets
The viscosity of dimethyl ether (DME, C2H6O) and of the fluorinated propene isomers 2,3,3,3- tetrafluoroprop-1-ene (R1234yf, C3H2F4) and trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) was measured in a combined temperature range from 242 K to 350 K at
William P. Krekelberg, Vincent K. Shen, Jeffrey R. Errington, Thomas M. Truskett
Using event-driven molecular dynamics simulations, we quantify how the self diffusivity of confined hard-sphere fluids depends on the nature of the confining boundaries. We explore systems with featureless confining boundaries that treat particle-boundary
F Case, Anne M. Chaka, Jonathan D. Moore, Raymond D. Mountain, Richard B. Ross, Vincent K. Shen, Eric A. Stahlberg
The sixth industrial fluid properties simulation challenge was held in 2010. The contestants were challenged to predict mutual solubility in liquid-liquid equilibria (LLE) for the PROGLYDE DMM + water system at various temperatures and atmospheric pressure