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Stretchable electronic conductors are vital components in soft robotics and flexible electronics. One method for producing these is combining conductive filler with a nonconductive elastomer. These composites commonly exhibit significant piezoresistivity. This work examines various mechanisms that may underlie this effect. These composites are generally analyzed through percolation theory, which describes the nonlinear relationship between filler volume fraction and conductivity. However, it is unclear whether percolation theory can explain their piezoresistivity or whether mechanisms such as rearrangement of the conductive network under deformation must be considered. This work compares volumetric change in the context of percolation theory against network rearrangement to examine the relative significance of these factors in determining piezoresistivity. Digital image correlation is utilized to investigate volumetric changes in carbon‐black silicone composites and finds that the typical assumption of incompressibility is reasonable, suggesting that volumetric changes alone cannot account for the behavior. A computational model is also developed, which implies that network rearrangement is likely a more significant factor and that interparticle interactions are crucial in understanding this effect. It was found that the most realistic modeling results were achieved only when both rigid and attractive interparticle interactions were accounted for in the model. [ABSTRACT FROM AUTHOR]

Abstract: State‐of‐the‐art relativistic coupled‐cluster theory is used to construct many‐body potentials for the noble‐gas element radon to determine its bulk properties including the solid‐to‐liquid phase transition from parallel tempering Monte Carlo simulations through either direct sampling of the bulk or from a finite cluster approach. The calculated melting temperature are 200(3) K and 200(6) K from bulk simulations and from extrapolation of finite cluster values, respectively. This is in excellent agreement with the often debated (but widely cited) and only available value of 202 K, dating back to measurements by Gray and Ramsay in 1909. [ABSTRACT FROM AUTHOR]

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Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The cohesive energies of argon in its cubic and hexagonal closed packed structures are computed with an unprecedented accuracy of about 5 J mol−1 (corresponding to 0.05 % of the total cohesive energy). The same relative accuracy with respect to experimental data is also found for the face-centered cubic lattice constant deviating by ca. 0.003 Å. This level of accuracy was enabled by using high-level theoretical, wave-function-based methods within a many-body decomposition of the interaction energy. Static contributions of two-, three-, and four-body fragments of the crystal are all individually converged to sub-J mol−1 accuracy and complemented by harmonic and anharmonic vibrational corrections. Computational chemistry is thus achieving or even surpassing experimental accuracy for the solid-state rare gases. [ABSTRACT FROM AUTHOR]

Argon unter Druck gesetzt: Ab ‐ initio ‐ Monte ‐ Carlo ‐ Simulationen überhitzter Argon ‐ Kristalle bei Drücken bis zu 100 GPa lassen den Schluss zu, dass Rechnungen genauere Beschreibungen von Hochdruck ‐ Schmelzübergängen zulassen als Experimente in Diamantstempelzellen. [ABSTRACT FROM AUTHOR]

Putting the bite on argon: Ab initio Monte Carlo simulations of superheated argon crystals at up to 100 GPa suggest that theory can provide a more accurate picture of high‐pressure melting than modern diamond‐anvil cell experiments. [ABSTRACT FROM AUTHOR]

Antwort auf ein altes Problem: Monte ‐ Carlo ‐ Simulationen mithilfe eines Diatomics ‐ in ‐ Molecules ‐ Modells, das aus exakten Rechnungen der Grundzustände und angeregten Zustände von Hg2 konstruiert wurde, zeigen, dass die Schmelztemperatur von kristallinem Quecksilber durch relativistische Effekte um 105 K gesenkt wird. [ABSTRACT FROM AUTHOR]

An old problem solved: Monte Carlo simulations using the diatomic‐in‐molecule method derived from accurate ground‐ and excited‐state relativistic calculations for Hg2 show that the melting temperature for bulk mercury is lowered by 105 K, which is due to relativistic effects. [ABSTRACT FROM AUTHOR]

Die allgemeine Relativitätstheorie lieferte die richtige Erklärung für die Präzession des Merkur ‐ Perihels. Wie F. Calvo, P. Schwerdtfeger et al. in der Zuschrift auf S. 7731 ff. demonstrieren, liefert die spezielle Relativitätstheorie ein sogar noch bemerkenswerteres Resultat, nämlich die richtige Erklärung dafür, dass Quecksilber (Mercurium) das einzige bei Raumtemperatur flüssige Metall ist, wie Monte ‐ Carlo ‐ Simulationen belegen (Bild: Cameron Smorenburg). [ABSTRACT FROM AUTHOR]

The generalized theory of relativity gives a correct explanation of the residual motion of the perihelion of planet mercury. As F. Calvo, P. Schwerdtfeger, et al. show in their Communication on page 7583 ff., the special theory of relativity has furnished an even more remarkable result. It gives the correct explanation as to why mercury is the only liquid metal at room temperature, as demonstrated by parallel‐tempering Monte Carlo simulations (Picture: Cameron Smorenburg). [ABSTRACT FROM AUTHOR]