Structure of water; A Monte Carlo calculation

Barker, John A.; Watts, R. O.

doi:10.1016/0009-2614(69)80119-3

Cited by 471 publications

(196 citation statements)

References 14 publications

Supporting

Mentioning

194

Contrasting

Unclassified

Order By: Relevance

“…In MC simulations, the degrees of freedom of surfactant molecules are sampled using displacement, 39 rotation, 40 and configurational-bias MC trial moves. [41][42][43][44] The rotational degrees of freedom of the individual NCs are sampled using rotations of the NC core or of the cluster defined as the NC with ligands adsorbed on its surface.…”

Section: Monte Carlo and Molecular Dynamics Simulationsmentioning

confidence: 99%

Understanding interactions between capped nanocrystals: Three-body and chain packing effects

Schapotschnikow

Vlugt

2009

The Journal of Chemical Physics

152

View full text Add to dashboard Cite

Self-assembly of capped nanocrystals ͑NC͒ attracted a lot of attention over the past decade. Despite progress in manufacturing of NC superstructures, the current understanding of their mechanical and thermodynamic stability is still limited. For further applications, it is crucial to find the origin and the magnitude of the interactions that keep self-assembled NCs together, and it is desirable to find a way to rationally manipulate these interactions. We report on molecular simulations of interacting gold NCs protected by capping molecules. We computed the potential of mean force for pairs and triplets of NCs of different size ͑1.8-3.7 nm͒ with varying ligand length ͑ethanethiol-dodecanethiol͒ in vacuum. Pair interactions are strongly attractive due to attractive van der Waals interactions between ligand molecules. Three-body interaction results in an energy penalty when the capping layers overlap pairwise. This effect contributes up to 20% to the total energy for short ligands. For longer ligands, the three-body effects are so large that formation of NC chains becomes energetically more favorable than close packing of capped NCs at low concentrations, in line with experimental observations. To explain the equilibrium distance for two or more NCs, the overlap cone model is introduced. This model is based on relatively simple ligand packing arguments. In particular, it can correctly explain why the equilibrium distance for a pair of capped NCs is always Ϸ1.25 times the core diameter independently on the ligand length, as found in our previous work ͓Schapotschnikow, R. Pool, and T. J. H. Vlugt, Nano Lett. 8, 2930 ͑2008͔͒. We make predictions for which ligands capped NCs self-assemble into highly stable three-dimensional structures, and for which they form high-quality monolayers.

show abstract

Section: Monte Carlo and Molecular Dynamics Simulationsmentioning

confidence: 99%

Understanding interactions between capped nanocrystals: Three-body and chain packing effects

Schapotschnikow

Vlugt

2009

The Journal of Chemical Physics

152

View full text Add to dashboard Cite

show abstract

“…On the computational side, the earliest atomistic simulations of the ambient liquid using a simple empirical potential were performed almost 40 years ago. 1 Since then, many improved potentials have been developed and shown to provide better agreement with experiment when used in classical molecular-dynamics and Monte Carlo simulations, [2][3][4][5][6][7][8] and these simulations have been extended to study the properties of liquid water in a much wider variety of regimes. [8][9][10][11][12] The first quantum-mechanical simulations of the static equilibrium properties of the liquid were performed in the mid-1980s, when the path-integral Monte Carlo ͑PIMC͒ method was used to assess the effect of quantummechanical fluctuations on the liquid structure.…”

Section: Introductionmentioning

confidence: 99%

Quantum diffusion in liquid water from ring polymer molecular dynamics

Miller

Manolopoulos²

2005

The Journal of Chemical Physics

205

190

View full text Add to dashboard Cite

We have used the ring polymer molecular-dynamics method to study the translational and orientational motions in an extended simple point charge model of liquid water under ambient conditions. We find, in agreement with previous studies, that quantum-mechanical effects increase the self-diffusion coefficient D and decrease the relaxation times around the principal axes of the water molecule by a factor of around 1.5. These results are consistent with a simple Stokes-Einstein picture of the molecular motion and suggest that the main effect of the quantum fluctuations is to decrease the viscosity of the liquid by about a third. We then go on to consider the system-size scaling of the calculated self-diffusion coefficient and show that an appropriate extrapolation to the limit of infinite system size increases D by a further factor of around 1.3 over the value obtained from a simulation of a system containing 216 water molecules. These findings are discussed in light of the widespread use of classical molecular-dynamics simulations of this sort of size to model the dynamics of aqueous systems.

show abstract

“…For each trial move, a particle was selected at random and subjected to a random trial displacement within a cube centred on the particle's original position. Where the selected particle was a rod, this displacement was combined with a random rotation implemented using the Barker-Watts method [17]. N such random MC moves made up one MC cycle, so that, on average, each particle experienced one trial move per cycle.…”

mentioning

confidence: 99%

Orientational and phase-coexistence behaviour of hard rod–sphere mixtures

Antypov¹,

Cleaver²

2003

Chemical Physics Letters

View full text Add to dashboard Cite

Results are presented from Monte Carlo simulations of bulk mixtures of Hard Gaussian Overlap particles with an aspect ratio of 3:1 and hard spheres with diameters equal to the breadths of the rods. For sphere number-concentrations of 50% and lower, compression of the isotropic fluid results in formation of a homogeneous (i.e. compositionally mixed) nematic phase. The volume fraction of this isotropicnematic transition is found to increase approximately linearly with sphere concentration. On compression to higher volume fractions, however, this homogeneous nematic phase separates out into coexisting nematic and isotropic phases.

show abstract

Structure of water; A Monte Carlo calculation

Cited by 471 publications

References 14 publications

Understanding interactions between capped nanocrystals: Three-body and chain packing effects

Understanding interactions between capped nanocrystals: Three-body and chain packing effects

Quantum diffusion in liquid water from ring polymer molecular dynamics

Orientational and phase-coexistence behaviour of hard rod–sphere mixtures

Contact Info

Product

Resources

About