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d-Mannitol belongs to a large and growing family of crystals with helical morphologies (Yu, L. J. Am. Chem. Soc.2003, 125, 6380). Two polymorphs of d-mannitol, α and δ, when grown in the presence of additives such as poly(vinylpyrrolidone) (PVP) or d-sorbitol, form ring-banded spherulites composed of handed helical fibrils, where the helix axes correspond to the radial growth directions. The two polymorphs form helices with opposite senses in the presence of PVP but the same sense in the presence of d-sorbitol. The characteristic dimensions of the fibrils, including thickness, aspect ratio, and pitch, were determined by scanning probe and electron microscopies. These values must form the basis of any theory that presupposes what forces give rise to crystal twisting, a problem that has been broached but unsettled in the literature of polymer crystallization. The interdependence of the rhythmic variations of both linear and circular birefringence, as determined by Mueller matrix microscopy, informs the cooperative organization of mannitol fibers. The microstructure of mannitol ring-banded spherulites compares favorably to that of high polymers and is evaluated within the context of current theories of crystal twisting.

The role of proton transfer in the photoluminescence intermittency (PI) of single molecules of violamine R (VR) overgrown in potassium acid phthalate (KAP) crystals is evaluated in comparisons of protonated (KAP) and deuterated (DKAP) mixed crystals between 23 and 60 °C. The PI is analyzed by the construction of cumulative distribution functions that are statistically compared. We find that the on- and off-interval duration distributions change with isotopic substitution consistent with proton transfer contributing to the PI of VR. The on- and off-interval duration distributions have distinct temperature dependencies consistent with different mechanisms for dark state production and decay. Additional evidence for proton-transfer is provided by distributions of single molecule emission-energy maxima that reflect emission from protonated and deprotonated VR. A mechanism for the PI of KAP is presented, where the dark state is assigned to formation of the colorless, leuco form of VR, formed by proton transfer from VR to the KAP lattice, and decay of the dark state involves ring-opening promoted by proton transfer from KAP to VR. The distributed kinetics for dark-state production and decay are modeled using a log-normal distribution for the PI data in preference to a power-law previously assumed. A discussion of the log-normal distribution with regards to PI and proton transfer is presented.

Various researchers recently reported that they had first controlled the mesoscale helicity of achiral crystals with the use of chiral additives. In fact, Wallerant showed in 1907 that resorcinol crystals, among others, grew from the melt as helical fibers whose sense of twist was determined by resolved additives. Wallerant’s demonstration is reproduced herein and his observations are given interpretation via computation of adsorption energetics through simulated annealing.

Disorder is a common feature of molecular crystals that complicates determination of structures and can potentially affect electric and mechanical properties. Suppression of disorder is observed in otherwise severely disordered benzamide and thiobenzamide crystals by substituting hydrogen with fluorine in the ortho-position of the phenyl ring. Fluorine occupancies of 20–30% are sufficient to suppress disorder without changing the packing motif. Crystal structure prediction calculations reveal a much denser lattice energy landscape for benzamide compared to 2-fluorobenzamide, suggesting that fluorine substitution makes disorder less likely.

The crystallization of a series of triisopropylsilylethynyl (TIPS)-derivatized acene-based organic semiconductors drop cast from solution onto substrates was investigated as a function of the size of their conjugated cores. When drop cast onto a substrate, the molecules in TIPS-pentacene crystals adopt a “horizontal” orientation, with the long axis of the pentacene core parallel to the substrate surface. For crystals comprising molecules with dibenzopyrene, anthanthrene, and pyranthrene cores, two-dimensional X-ray diffraction patterns revealed the existence of a second population of crystals adopting a “vertical” molecular orientation with the long axis of the acene core perpendicular to the substrate surface. The ratio of the population of TIPS-pyranthrene crystals with molecules adopting horizontal versus vertical orientations was controlled by varying the surface energy of the underlying substrate. These crystals displayed orientation-dependent linear birefringence and linear dichroism, as observed by differential polarizing optical microscopy. Conductive atomic force microscopy (C-AFM) revealed a 42-fold improvement in out-of-plane hole mobility through crystals adopting the vertical molecular orientation compared to those adopting the horizontal molecular orientation.

Microscopic inclusions are common sources of dislocations in solution-grown crystals, but the correspondence between the size and shape of inclusions and the probability of dislocation generation has not been established quantitatively. This correspondence is obtained herein through the use of spherical poly(styrene) particles with well-defined diameters, ranging from 1 to 90 μm, which were incorporated within potassium hydrogen phthalate crystals during growth from solution. The probability of generating dislocations by particle overgrowth increased with increasing supersaturation and particle size. The largest particles generate so many dislocations that daughter crystals emerge that are no longer in single-crystal register with the host. The results are consistent with a model that depends on surmounting the elastic energy of crystal layers associated with bending. Dislocation generation during the last stages of overgrowth is favored when the height difference between the growing layer and the particle protruding from the crystal surface is larger than a dislocation Burgers vector and the angle between the crystal surface and the particle surface is small enough that the growth layer can bend as it climbs onto the particle.

Mueller matrix polarimetry is a powerful optical technique for characterization of both anisotropic and bianisotropic materials. This review emphasizes methods for the interpretation of measured Mueller matrices, from the meanings of matrix symmetries, to ab initio calculations of Mueller matrices that begin with Maxwell’s equations operating on materials with permittivity, permeability, and magnetoelectric constitutive tensors. We present an overview of polarimetry measurements in crystals as well as metamaterials that have optically responsive features on the order of the wavelength of visible light. Examples of the full measurement of the constitutive tensors of bianisotropic media from the analysis of their Mueller matrices, collected in either transmission or reflection, are illustrated for natural crystals, polycrystals, and nanofabricated metamaterials. Experimental and theoretical research into the complex optical responses of bianisotropic materials with polarized light is best expressed in terms of the Mueller matrix, as it offers an unambiguous and mathematically robust platform for analysis of light–matter interactions.

In this work, the effect of Cr3+partial substitution on vanadium site in monoclinic lithium vanadium(III) phosphate (LVP) structure resulting in compounds with general formula: Li3V2-xCrx(PO4)3-C (x= 0, 0.05, 0.1, 0.15) was studied. A two-step sol-gel combustion method was employed in syntheses. The samples were characterized by X-ray powder diffraction, scanning electron microscopy, coupled plasma optical emission spectroscopy, and flash combustion. The electrochemical performance of the active materials was examined through rate capability tests and cyclic voltammetry. The unsubstituted compound LVPC delivers higher capacity compared to the Cr-containing samples due to chromium inactivity in the potential range 3.0–4.4 V vs. Li/Li+. However, the Cr-substituted materials show better overall capacity retention (97–97.6%) in contrast to Li3V2(PO4)3-C (96%) in long cycling.

Contact insecticides often involve the interaction of whole organisms and toxicant crystal surfaces. The crystalline phase of these compounds has not, however, been considered for the optimization of insecticide performance. Lindane (1R,2r,3S,4R,5r,6S-hexachlorocyclohexane) has been one of the most widely used insecticides, but other (inactive) stereoisomers accompanying its manufacture have led to massive chemical waste remediation problems. Crystalline polymorphs are also isomers in the broadest sense, yet only one crystal structure of lindane has been reported. Herein, we report the discovery and characterization of two new polymorphs, Forms II and III. The efficacy of Forms I, II, and III against Drosophila melanogasterrevealed an inverse correlation between lethality and thermodynamic stability; the least stable kills fastest. This understanding provides a crystal engineering opportunity wherein formulations containing the most active contact insecticide polymorph can achieve infectious disease prophylaxis while reducing environmental exposure and associated chemical waste.

Despite considerable progress of silicon/carbon (Si/C) composites anodes, they still suffer from high irreversible capacity losses, which are mainly due to continuous Solid Electrolyte Interphase (SEI) layer formation, which consumes a large amount of lithium. To compensate for the active lithium losses, prelithiation of Si-based anodes has been attempted. In this manuscript, we report the effect of prelithiation on Si/C anodes combined with LiNi0.5Mn0.3Co0.2O2 cathodes in full cell configurations. To prepare LixSi/C anodes, Si/C electrodes were lithiated electrochemically at 0.1 and 0.5 V vs. Li/Li+ in half cell configuration before assembly of the full cell. Special attention is paid to the effect of the degree of prelithiation on initial electrochemical behavior and Li dendrite formation. In this work, electrochemical investigations were performed by using two-electrode and three-electrode measurements. Furthermore, the morphology of the active materials before and after cycling were characterized by post mortem Scanning Electron Microscopy (SEM).

Well-formed crystals are polyhedral with flat facets and sharp edges. Nevertheless, a remarkable number of molecular crystals can bend and twist during growth. Many others can be distorted by applying external forces or creating heterogeneities by temperature gradient or photochemical reaction. As part of an effort to identify the forces that so commonly deform molecular crystals and to characterize their consequences, a force field is evaluated for its ability to predict mechanical distortions in nanocrystals. Macroscopic materials provide estimates of the expected responses that were tested here in silico for “molecular bimetallic strips” created from rods of iodoform and bromoform in smooth contact and nanocrystalline rods of iodoform with left and right screw dislocations. It was demonstrated that an optimized force field based largely on AMBER parameters matches expectations for elastic and plastic distortions, despite the fact that these mechanical responses are far removed from the force field parametrization set.

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Zusammenfassung.Die konstriktive Perikarditis stellt als seltene und gefürchtete Komplikation einer akuten Perikarditis eine schwere und ungewöhnliche Form einer diastolischen Herzinsuffizienz dar bei primär erhaltener systolischer Pumpfunktion. Häufigste Ursache ist die virale/idiopathische Perikarditis, gefolgt von spezifischen Ursachen (postoperativ nach herzchirurgischer Operation, postaktinisch nach mediastinaler Radiotherapie und weitere Ursachen). Durch das steife, unelastische Perikard ist die diastolische Füllung des Herzens eingeschränkt, was zum klinischen Bild einer Rechtsherzinsuffizienz führt und sich mit erhöhten Füllungsdrücken und spezifischen respiratorischen Phänomenen in der klinischen und apparativ-technischen Untersuchung manifestiert (Kussmaul-Zeichen, Pulsus paradoxus, vermehrte interventrikuläre Interdependenz, Annulus reversus, Quadratwurzelzeichen). Differenzialdiagnostisch müssen die restriktive Kardiomyopathie, die schwere Trikuspidalinsuffizienz und die Perikardtamponade ausgeschlossen werden. Die Therapie der Wahl ist zumeist eine chirurgische Perikardektomie, in Einzelfällen kann auch eine spezifische Therapie oder eine medikamentös-antiinflammatorische Therapie erfolgen. Obwohl die konstriktive Perikarditis unbehandelt eine schlechte Prognose hat, ist die Erkrankung potenziell kurativ therapierbar. Die Prognose ist vor allem von der Ursache der konstriktiven Perikarditis abhängig.

All-solid-state lithium-ion batteries are considered as a promising electric energy storage platform for electric vehicles due to the replacement of flammable liquid organic electrolytes in current lithium-ion batteries by inflammable solid ones; thus promoting high safety. Despite plenty of research on various solid electrolytes and other components, reports on the scalable production of all-solid-state lithium-ion batteries using electrodes with meaningful areal capacities are rather scarce. Consequently, the safety of all-solid-state lithium-ion batteries has not been systematically investigated yet, especially on cells with higher than lab-scale capacities. The aim of this report is to build a bridge between academic research and more industrially meaningful information on the safety of all-solid-state lithium-ion batteries. Thus, three 1Ah all-solid-state lithium-ion batteries were fabricated, where hybrid solid electrolyte consisting of PEO-LiTFSI polymer matrix with Lithium Ionic Conductive Glass Ceramic (LICGC™, Ohara Inc.) particle as active filler was sandwiched between NMC622 cathode and advanced graphite MCMB anode, both of which have a practically valuable areal capacity of higher than 1.0 mAh/cm2. Initial formation cycling was performed to build conformal interface between solid electrolyte film and electrodes. Comparable specific capacity of cathode active materials (∼90.0 mAh/g @ C/10 & 60 °C) could be achieved in three pouch cells with high consistence. Typical abuse tests including overcharge, external short, and nail penetration were conducted, the three 1Ah all-solid-state lithium-ion batteries cells showed excellent safety performance: there was no thermal runaway, no explosion, only slight increase of temperature was observed. This work demonstrates the scalable fabrication of practical all-solid-state lithium-ion batteries with consistent electrochemical performance and thereafter confirms their intrinsic safety.