Entanglement via rotational blockade of MgF molecules in a magic potential

Liquid crystals (LCs), owing to their anisotropy in molecular ordering, are of wide interest in both the display industry and soft matter as a route to more sophisticated optical objects, to direct phase separation, and to facilitate colloidal assemblies. However, it remains challenging to directly probe the molecular-scale organization of nonglassy nematic LC molecules without altering the LC directors. We design and synthesize a new type of nematic liquid crystal monomer (LCM) system with strong dipole–dipole interactions, resulting in a stable nematic phase and strong homeotropic anchoring on silica surfaces. Upon photopolymerization, the director field can be faithfully “locked,” allowing for direct visualization of the LC director field and defect structures by scanning electron microscopy (SEM) in real space with 100-nm resolution. Using this technique, we study the nematic textures in more complex LC/colloidal systems and calculate the extrapolation length of the LCM.

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Cation-anion pairs of niobium clusters of the type [Nb6Cl12(RCN)6][Nb6Cl18] (R=Et, nPr, iPr) with nitrile ligands RCN forming stabilizing inter-ionic contacts

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0177 ◽

2020 ◽

Vol 75 (1-2) ◽

pp. 173-181

Author(s):

Eric Sperlich ◽

Martin Köckerling

Keyword(s):

Cluster Compounds ◽

Cluster Ions ◽

Cluster Anions ◽

Dipole Interactions ◽

Average Oxidation State ◽

Metal Atoms ◽

Cluster Cation ◽

Acid Anhydrides ◽

Strong Dipole ◽

Positively Charged

AbstractThree new niobium cluster compounds with edge bridged, octahedral hexanuclear metal cores have been synthesised. They consist of cluster pairs with [Nb6Cl12(RCN)6]2+ cations, [Nb6Cl18]2− anions, and co-crystallised nitrile molecules, with R = C2H5 (propionitrile), nC3H7 (butyronitrile), iC3H7 (isobutyronitrile). The synthesis is based on the dehydration of [Nb6Cl14(H2O)4] · 4(H2O) with carboxylic acid anhydrides in the presences of an excess of the respective nitrile. An interesting aspect of these compounds is that the metal atoms of the cluster cation have an average oxidation state different from that of the cluster anion, the former being oxidized losing two electrons. In crystals of all three compounds layers of cluster cations are separated by layers of cluster anions. Perpendicular to these layers of the same cluster types, every cation is surrounded by four anions and vice versa. Between the cations and anions short distances are found between the halogenido ligands and the positively charged C atoms of the nitrile ligands (N–C · · · Cl angles of ~90°). These contacts indicate relatively strong dipole-dipole interactions, which presumably contribute to the arrangement of the cluster ions in the crystals.

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Green's Function Theory of a Heisenberg Ferromagnet with Strong Dipole-Dipole Interactions: Magnetization of GdCl3

Physical Review B ◽

10.1103/physrevb.1.314 ◽

1970 ◽

Vol 1 (1) ◽

pp. 314-318 ◽

Cited By ~ 9

Author(s):

Egon Becker ◽

Michael Plischke

Keyword(s):

Green’S Function ◽

Green's Function ◽

Function Theory ◽

Heisenberg Ferromagnet ◽

Dipole Interactions ◽

Strong Dipole

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Effect of Central Longitudinal Dipole Interactions on Chiral Liquid-Crystal Phases

International Journal of Molecular Sciences ◽

10.3390/ijms19092715 ◽

2018 ◽

Vol 19 (9) ◽

pp. 2715 ◽

Cited By ~ 4

Author(s):

Takuma Nozawa ◽

Paul Brumby ◽

Kenji Yasuoka

Keyword(s):

Liquid Crystals ◽

Phase Behavior ◽

Coarse Grained ◽

Systematic Analysis ◽

Dipole Interactions ◽

Liquid Phases ◽

Systematic Understanding ◽

Chiral Systems ◽

Chiral Liquid Crystals ◽

Strong Dipole

Monte Carlo simulations of chiral liquid-crystals, represented by a simple coarse-grained chiral Gay–Berne model, were performed to investigate the effect of central longitudinal dipole interactions on phase behavior. A systematic analysis of the structural properties and phase behavior of both achiral and chiral systems, with dipole interactions, reveals differing effects; strong dipole interactions enhance the formation of layered structures; however, chiral interactions may prevent the formation of such phases under certain conditions. We also observed a short-ranged smectic structure within the cholesteric phases with strong dipole interactions. This constitutes possible evidence of presmectic ordering and/or the existence of chiral line liquid phases, which have previously been observed in X-ray experiments to occur between the smectic twisted grain boundary and cholesteric phases. These results provide a systematic understanding of how the phase behavior of chiral liquid-crystals changes when alterations are made to the strength of dipole interactions.

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Sedimentation equilibrium of magnetic nanoparticles with strong dipole-dipole interactions

Physical Review E ◽

10.1103/physreve.95.032609 ◽

2017 ◽

Vol 95 (3) ◽

Cited By ~ 2

Author(s):

Andrey A. Kuznetsov ◽

Alexander F. Pshenichnikov

Keyword(s):

Magnetic Nanoparticles ◽

Sedimentation Equilibrium ◽

Dipole Interactions ◽

Strong Dipole

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Dipolar condensed atomic mixtures and miscibility under rotation

SciPost Physics Proceedings ◽

10.21468/scipostphysproc.3.023 ◽

2020 ◽

Author(s):

Lauro Tomio ◽

Ramavarmaraja Kishor Kumar ◽

Arnaldo Gammal

Keyword(s):

Binary Mixtures ◽

Spatial Separation ◽

Pitaevskii Equation ◽

Polarization Angle ◽

Two Dimensional ◽

Dipole Interactions ◽

Quartic Term ◽

Vortex Patterns ◽

Bose Einstein ◽

Dipole Polarization

By considering symmetric- and asymmetric-dipolar coupled mixtures (with dysprosium and erbium isotopes), we report a study on relevant anisotropic effects, related to spatial separation and miscibility, due to dipole-dipole interactions (DDIs) in rotating binary dipolar Bose-Einstein condensates. The binary mixtures are kept in strong pancake-like traps, with repulsive two-body interactions modeled by an effective two-dimensional (2D) coupled Gross-Pitaevskii equation. The DDI are tuned from repulsive to attractive by varying the dipole polarization angle. A clear spatial separation is verified in the densities for attractive DDIs, being angular for symmetric mixtures and radial for asymmetric ones. Also relevant is the mass-imbalance sensibility observed by the vortex-patterns in symmetric- and asymmetric-dipolar mixtures. In an extension of this study, here we show how the rotational properties and spatial separation of these dipolar mixture are affected by a quartic term added to the harmonic trap of one of the components.

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