ABSTRACT Monodisperse colloidal suspensions of ligand-coated silicon nanocrystals (SiNCs), synthe... more ABSTRACT Monodisperse colloidal suspensions of ligand-coated silicon nanocrystals (SiNCs), synthesized through a nonthermal low-pressure plasma reaction, are prepared through density-gradient ultracentrifugation in mixed organic solvents. The SiNC fractions are then self-assembled into close-packed quantum-dot ``solids'' and clusters, and photoluminescent properties of the resulting ordered ensembles are characterized through optical spectroscopy. We find striking manifestations of particle-particle interactions in the measured optical response, and we model these effects using Monte Carlo simulations of the photobleaching kinetics in dense SiNC packings.
Recently, particle based simulation methods have started to play an important role in studies of ... more Recently, particle based simulation methods have started to play an important role in studies of rarefied gas flows, and dynamics of complex liquids such as polymer solutions and colloidal suspensions. In rare gases, their main advantage is in the moderate Knudsen number regime, where traditional methods fail. They are used to model complex liquids because it is easy to couple to embedded particles or macromolecules, they incorporate thermal fluctuations, and are easily implemented in complex geometries. We will describe a new method called the stochastic rotation dynamics, which is similar to Direct Simulation Monte Carlo (DSMC), but employs efficient multiparticle collisions. Analytical expressions for the transport coefficients in three dimensions will be presented and compared with the simulation results. In particular, their dependence of lambda/a, where lambda is the mean free path and a is the size of the cells introduced to define the collision environment, will be discussed. Possible future applications and the method's advantages compared to traditional particle-based methods will also be addressed.
APS Bulletin of the American Physical Society. APS March Meeting 2012 Volume 57, Number 1. Monday... more APS Bulletin of the American Physical Society. APS March Meeting 2012 Volume 57, Number 1. Monday–Friday, February 27–March 2 2012; Boston, Massachusetts. ...
We explore the feasibility of determining the surface interaction couplings in binary alloys usin... more We explore the feasibility of determining the surface interaction couplings in binary alloys using a combination of diffuse x-ray surface and bulk scattering. For this purpose we extend the Clapp-Moss approach to include surface-specific short-range order. On the basis of this theory and from tests with simulation data, we conclude that the suggested method is promising and appears to be sufficiently sensitive to determine the surface couplings to an accuracy of 10-20 %, provided that the background corrections from thermal diffuse and defect scattering can be reliably controlled.
A Comment on the Letter by K. Binder, DP Landau, and DM Kroll Phys. Rev. Lett. 56, 2272 (1986). .... more A Comment on the Letter by K. Binder, DP Landau, and DM Kroll Phys. Rev. Lett. 56, 2272 (1986). ... (Some reference links may require a separate subscription.) ... E. Brézin et al., Phys. Rev. Lett. 50, 1387 (1983) [SPIN];[INSPEC]. ... (a) K. Binder, DP Landau and DM ...
Comparison of weighted-density-functional theories for inhomogeneous liquids. DM Kroll and Brian ... more Comparison of weighted-density-functional theories for inhomogeneous liquids. DM Kroll and Brian B. Laird Institut für Festkörperforschung des Forschungszentrums Jülich, Postfach 1913, 5170 Jülich, West Germany. Received 22 May 1990 ...
ABSTRACT Monodisperse colloidal suspensions of ligand-coated silicon nanocrystals (SiNCs), synthe... more ABSTRACT Monodisperse colloidal suspensions of ligand-coated silicon nanocrystals (SiNCs), synthesized through a nonthermal low-pressure plasma reaction, are prepared through density-gradient ultracentrifugation in mixed organic solvents. The SiNC fractions are then self-assembled into close-packed quantum-dot ``solids'' and clusters, and photoluminescent properties of the resulting ordered ensembles are characterized through optical spectroscopy. We find striking manifestations of particle-particle interactions in the measured optical response, and we model these effects using Monte Carlo simulations of the photobleaching kinetics in dense SiNC packings.
Recently, particle based simulation methods have started to play an important role in studies of ... more Recently, particle based simulation methods have started to play an important role in studies of rarefied gas flows, and dynamics of complex liquids such as polymer solutions and colloidal suspensions. In rare gases, their main advantage is in the moderate Knudsen number regime, where traditional methods fail. They are used to model complex liquids because it is easy to couple to embedded particles or macromolecules, they incorporate thermal fluctuations, and are easily implemented in complex geometries. We will describe a new method called the stochastic rotation dynamics, which is similar to Direct Simulation Monte Carlo (DSMC), but employs efficient multiparticle collisions. Analytical expressions for the transport coefficients in three dimensions will be presented and compared with the simulation results. In particular, their dependence of lambda/a, where lambda is the mean free path and a is the size of the cells introduced to define the collision environment, will be discussed. Possible future applications and the method's advantages compared to traditional particle-based methods will also be addressed.
APS Bulletin of the American Physical Society. APS March Meeting 2012 Volume 57, Number 1. Monday... more APS Bulletin of the American Physical Society. APS March Meeting 2012 Volume 57, Number 1. Monday–Friday, February 27–March 2 2012; Boston, Massachusetts. ...
We explore the feasibility of determining the surface interaction couplings in binary alloys usin... more We explore the feasibility of determining the surface interaction couplings in binary alloys using a combination of diffuse x-ray surface and bulk scattering. For this purpose we extend the Clapp-Moss approach to include surface-specific short-range order. On the basis of this theory and from tests with simulation data, we conclude that the suggested method is promising and appears to be sufficiently sensitive to determine the surface couplings to an accuracy of 10-20 %, provided that the background corrections from thermal diffuse and defect scattering can be reliably controlled.
A Comment on the Letter by K. Binder, DP Landau, and DM Kroll Phys. Rev. Lett. 56, 2272 (1986). .... more A Comment on the Letter by K. Binder, DP Landau, and DM Kroll Phys. Rev. Lett. 56, 2272 (1986). ... (Some reference links may require a separate subscription.) ... E. Brézin et al., Phys. Rev. Lett. 50, 1387 (1983) [SPIN];[INSPEC]. ... (a) K. Binder, DP Landau and DM ...
Comparison of weighted-density-functional theories for inhomogeneous liquids. DM Kroll and Brian ... more Comparison of weighted-density-functional theories for inhomogeneous liquids. DM Kroll and Brian B. Laird Institut für Festkörperforschung des Forschungszentrums Jülich, Postfach 1913, 5170 Jülich, West Germany. Received 22 May 1990 ...
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