Plenty of room at the top

Frenkel, Daan

doi:10.1038/nmat1572

Cited by 23 publications

(24 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thermodynamic stability of crystals is a topic of growing importance to a number of solid-state and nano-material applications of molecular modeling. This includes molecular crystals, 1,2 (especially pharmaceuticals 3 ), alloys, 4, 5 refractory materials, 6 clathrate hydrates, 7 colloids, 8,9 nanoparticles, [10][11][12][13] and more. Some of these systems are amenable to the application of ab initio methods for calculating the molecular energy, and thus promise a first-principles approach to prediction of stable crystal structures.…”

Section: Introductionmentioning

confidence: 99%

A comparative study of methods to compute the free energy of an ordered assembly by molecular simulation

Moustafa

Schultz

Kofke

2013

The Journal of Chemical Physics

View full text Add to dashboard Cite

We present a comparative study of methods to compute the absolute free energy of a crystalline assembly of hard particles by molecular simulation. We consider all combinations of three choices defining the methodology: (1) the reference system: Einstein crystal (EC), interacting harmonic (IH), or r(-12) soft spheres (SS); (2) the integration path: Frenkel-Ladd (FL) or penetrable ramp (PR); and (3) the free-energy method: overlap-sampling free-energy perturbation (OS) or thermodynamic integration (TI). We apply the methods to FCC hard spheres at the melting state. The study shows that, in the best cases, OS and TI are roughly equivalent in efficiency, with a slight advantage to TI. We also examine the multistate Bennett acceptance ratio method, and find that it offers no advantage for this particular application. The PR path shows advantage in general over FL, providing results of the same precision with 2-9 times less computation, depending on the choice of a common reference. The best combination for the FL path is TI+EC, which is how the FL method is usually implemented. For the PR path, the SS system (with either TI or OS) proves to be most effective; it gives equivalent precision to TI+FL+EC with about 6 times less computation (or 12 times less, if discounting the computational effort required to establish the SS reference free energy). Both the SS and IH references show great advantage in capturing finite-size effects, providing a variation in free-energy difference with system size that is about 10 times less than EC. This result further confirms previous work for soft-particle crystals, and suggests that free-energy calculations for a structured assembly be performed using a hybrid method, in which the finite-system free-energy difference is added to the extrapolated (1/N→0) absolute free energy of the reference system, to obtain a result that is nearly independent of system size.

show abstract

Section: Introductionmentioning

confidence: 99%

A comparative study of methods to compute the free energy of an ordered assembly by molecular simulation

Moustafa

Schultz

Kofke

2013

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…These NCs can self-assemble in a range of different 2D and 3D superstructures. [1][2][3] NCs are often protected by an organic capping layer of surfactants that prevents aggregation; 4 for example, gold NCs are often capped with alkyl thiol molecules. [5][6][7][8] Furthermore, adding surfactants during colloidal synthesis allows for control of the size and shape of the formed NCs.…”

Section: Introductionmentioning

confidence: 99%

Solvent Effects in the Adsorption of Alkyl Thiols on Gold Structures: A Molecular Simulation Study

2007

View full text Add to dashboard Cite

We carried out Monte Carlo simulations of gold nanocrystals (NCs) and (111) slabs covered with alkyl thiols, with and without explicit solvent (n-hexane), at T ) 300 K. Adsorption isotherms for propane-and octanethiol showed a phase behavior measured previously in experiments. Comparison of the adsorption isotherm of octanethiol in hexane on a (111) slab with experimental data suggests that, in this system, no thiolate bond was formed. The geometry of a gold surface strongly influences the formation and structure of the capping monolayer. On a (111) surface, attractive interactions between carbon chains are more pronounced than on a NC. This leads to a stronger penetration of the capping layer by the solvent. Adsorption selectivity for binary alkyl thiol mixtures is stronger in vacuum than in solution. The convex shape of the NCs also reduces the adsorption selectivity of binary thiol mixtures. This result shows that the solvent cannot be ignored in simulations.

show abstract

“…For example, just by varying the relative sizes of the two types of particles, surprisingly complex crystals can be formed. 6,7 Very recently, the use of particles with charges of opposite signs has led to colloidal 8,9 and nanoparticle 10,11,12 analogues of ionic crystals, even relatively low-density structures such as zinc blende.…”

mentioning

confidence: 99%

Controlling crystallization and its absence: proteins, colloids and patchy models

Doye

Louis²,

Lin

et al. 2007

Phys. Chem. Chem. Phys.

189

216

View full text Add to dashboard Cite

The ability to control the crystallization behaviour (including its absence) of particles, be they biomolecules such as globular proteins, inorganic colloids, nanoparticles, or metal atoms in an alloy, is of both fundamental and technological importance. Much can be learnt from the exquisite control that biological systems exert over the behaviour of proteins, where protein crystallization and aggregation are generally suppressed, but where in particular instances complex crystalline assemblies can be formed that have a functional purpose. We also explore the insights that can be obtained from computational modelling, focussing on the subtle interplay between the interparticle interactions, the preferred local order and the resulting crystallization kinetics. In particular, we highlight the role played by "frustration", where there is an incompatibility between the preferred local order and the global crystalline order, using examples from atomic glass formers and model anisotropic particles.

show abstract

Plenty of room at the top

Cited by 23 publications

References 9 publications

A comparative study of methods to compute the free energy of an ordered assembly by molecular simulation

A comparative study of methods to compute the free energy of an ordered assembly by molecular simulation

Solvent Effects in the Adsorption of Alkyl Thiols on Gold Structures: A Molecular Simulation Study

Controlling crystallization and its absence: proteins, colloids and patchy models

Contact Info

Product

Resources

About