Shaping the Future of Solid-State Electrolytes through Computational Modeling.

Advances and progress in computational research that aims to understand and improve solid-state electrolytes (SSEs) are outlined. One of the main challenges in the development of all-solid-state batteries is the design of new SSEs with high ion diffusivity that maintain chemical and phase stability and thereby provide a wide electrochemical stability window. Solving this problem requires a deep understanding of the diffusion mechanism and properties of the SSEs.

Influence of Constraints within a Cyclic Polymer on Solution Properties.

Cyclic polymers with internal constraints provide new insight into polymer properties in solution and bulk and can serve as a model system to explain the stability and mobility of cyclic biomacromolecules. The model system used in this work consisted of cyclic polystyrene structures, all with a nearly identical molecular weight, designed with 0-3 constraints located at strategic sites within the cyclic polymer, with either 4 or 6 branch points. The total number of branch points (or arms) within the cyclic ranged from 0 to 18.

Free Energy Calculations with Reduced Potential Cutoff Radii.

The Jarzynski Equality, the Crooks Fluctuation Theorem, and the Maximum Likelihood Estimator use a nonequilibrium approach for the determination of free energy differences due to a change in the state of a system. Here, this approach is used in combination with a novel transformation algorithm to increase computational efficiency in simulations with interacting particles, without losing accuracy. The algorithm is shown to work well for a Lennard-Jones fluid undergoing a change in density over three very different density ranges, and for the systems considered the algorithm demonstrates computational savings of up to approximately 90%.

A local dissipation theorem.

The transient time correlation function is a standard method for measuring transport properties in simulations. It represents a special case of a more general theorem, the dissipation theorem, that indirectly calculates phase function averages though the use of the dissipation function. These indirect averages often have significantly less statistical error than direct averages.

The free energy of expansion and contraction: treatment of arbitrary systems using the Jarzynski equality.

Thermodynamic integration, free energy perturbation, and slow change techniques have long been utilised in the calculation of free energy differences between two states of a system that has undergone some transformation. With the introduction of the Jarzynski equality and the Crooks relation, new approaches are possible. This paper investigates an important phenomenon - systems undergoing a change in volume/density - and derives both the Jarzynski equality and Crooks relation of such systems using a statistical mechanical approach.

Communication: Beyond Boltzmann's H-theorem: demonstration of the relaxation theorem for a non-monotonic approach to equilibrium.

Relaxation of a system to equilibrium is as ubiquitous, essential, and as poorly quantified as any phenomena in physics. For over a century, the most precise description of relaxation has been Boltzmann's H-theorem, predicting that a uniform ideal gas will relax monotonically. Recently, the relaxation theorem has shown that the approach to equilibrium can be quantified in terms of the dissipation function first defined in the proof of the Evans-Searles fluctuation theorem.

Different approaches for evaluating exponentially weighted nonequilibrium relations.

The Kawasaki identity (KI) and the Jarzynski equality (JE) are important nonequilibrium relations. Both of these relations take the form of an ensemble average of an exponential function and can exhibit convergence problems when the average of the exponent differs greatly from the log of the average of the exponential function. In this work, we re-express these relations so that only selected regions need to be evaluated in an attempt to avoid these convergence issues.