To date, trial and error strategies guided by intuition have dominated the identification of materials suitable for a specific application. We are entering a data-rich, modelling-driven era where such Edisonian approaches are gradually being replaced by rational strategies, which couple predictions from advanced computational screening with targeted experimental synthesis and validation. Here, consistent with this emerging paradigm, we propose a strategy of hierarchical modelling with successive downselection stages to accelerate the identification of polymer dielectrics that have the potential to surpass 'standard' materials for a given application. Successful synthesis and testing of some of the most promising identified polymers and the measured attractive dielectric properties (which are in quantitative agreement with predictions) strongly supports the proposed approach to material selection.

Electrostatic interactions between dielectric objects are complex and of a many-body nature, owing to induced surface bound charge. We present a collection of techniques to simulate dynamical dielectric objects. We calculate the surface bound charge from a matrix equation using the Generalized Minimal Residue method (GMRES). Empirically, we find that GMRES converges very quickly. Indeed, our detailed analysis suggests that the relevant matrix has a very compact spectrum for all non-degenerate dielectric geometries. Each GMRES iteration can be evaluated using a fast Ewald solver with cost that scales linearly or near-linearly in the number of surface charge elements. We analyze several previously proposed methods for calculating the bound charge, and show that our approach compares favorably.

We use simulations and experiments to delineate the mechanism by which the addition of a small number of polar −OH groups to a nonpolar polymer increases the static relative permittivity (or dielectric constant) by a factor of 2, but more importantly while keeping the dielectric loss in the frequency regime of interest to power electronics to less than 1%. Dielectric properties obtained from experiments on functionalized polyethylenes and polypropylenes as a function of −OH doping are in quantitative agreement with one another. Molecular dynamics simulations for the static relative permittivity of “dry” −OH functionalized polyethylene (in the absence of water) are apparently in quantitative agreement with experiments. However, these simulation results would further imply that there should be considerable dielectric loss beyond simulation time scales (>0.1 μs). Since there are minimal experimentally observed dielectric losses for times as short as a microsecond, we believe that a small amount of adsorbed water plays a critical role in this attenuated loss. We use simulations to derive the water concentration at saturation, and our results for this quantity are also in good agreement with experiments. Simulations of the static relative permittivity of PE–OH incorporating this quantity of hydration water are found to be in quantitative agreement with experiments when it is assumed that all the dipolar relaxations occur at time scales faster than 0.1 μs. These results suggest that improved polymeric dielectric materials can be designed by including −OH groups on the chain, but the mechanism requires the presence of a stoichiometric quantity of hydration water.

Tetrapods are among the most promising building blocks for nanoscale self-assembly, offering various desirable features. Whereas these particles can be fabricated with remarkable precision, comparatively less is known about their aggregation behavior. Employing a novel, powerful simulation method, we demonstrate that charged nanoparticles offer considerable control over the assembly of tip-functionalized tetrapods. Extending these findings to tetrapods confined to a gas/liquid interface, we show that regular structures can be achieved even without functionalization.

We extend the geometric cluster algorithm [J. Liu and E. Luijten, Phys. Rev. Lett. 92, 035504 (2004)], a highly efficient, rejection-free Monte Carlo scheme for fluids and colloidal suspensions, to the case of anisotropic particles. This is made possible by adopting hyperspherical boundary conditions. A detailed derivation of the algorithm is presented, along with extensive implementation details as well as benchmark results. We describe how the quaternion notation is particularly suitable for the four-dimensional geometric operations employed in the algorithm. We present results for asymmetric Lennard-Jones dimers and for the Yukawa one-component plasma in hyperspherical geometry. The efficiency gain that can be achieved compared to conventional, Metropolis-type Monte Carlo simulations is investigated for rod–sphere mixtures as a function of rod aspect ratio, rod–sphere diameter ratio, and rod concentration. The effect of curved geometry on physical properties is addressed.