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Muragishi R, Sato M. Structures Formed by Particles with Shoulderlike Repulsive Interaction in Thin Systems. ACS OMEGA 2023; 8:30450-30458. [PMID: 37636963 PMCID: PMC10448489 DOI: 10.1021/acsomega.3c03624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/25/2023] [Indexed: 08/29/2023]
Abstract
When particles are constructed in thin systems between two parallel flat walls, structures that are not observed in bulk systems are created and the created structures change, depending on the width between the walls. In this study, the structures formed by particles constructed in thin systems were investigated through performing isothermal-isobaric Monte Carlo simulations, where the interaction between the particles is given by the hard-core square shoulder potential. By controlling the width of the shoulder-like repulsive interaction and the system width, several novel structures such as the connection of rhombuses and the square lattice of the (100) face of the body-centered cubic lattice were created.
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Affiliation(s)
- Ryo Muragishi
- Graduate
School of Natural Science and Technology, Kanazawa University, 920-1192 Kanazawa, Japan
| | - Masahide Sato
- Emerging
Media Initiative, Kanazawa University, 920-1192 Kanazawa, Japan
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2
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Zampetaki AV, Huang H, Du CR, Löwen H, Ivlev AV. Buckling of two-dimensional plasma crystals with nonreciprocal interactions. Phys Rev E 2020; 102:043204. [PMID: 33212619 DOI: 10.1103/physreve.102.043204] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/15/2020] [Indexed: 11/07/2022]
Abstract
Laboratory realizations of two-dimensional (2D) plasma crystals typically involve monodisperse microparticles confined into horizontal monolayers in radio-frequency (rf) plasma sheaths. This gives rise to the so-called plasma wakes beneath the microparticles. The presence of wakes renders the interactions in such systems nonreciprocal, a fact that can lead to a quite different behavior from the one expected for their reciprocal counterparts. Here we examine the buckling of a hexagonal 2D plasma crystal, occurring as the confinement strength is decreased, taking explicitly into account the nonreciprocity of the system via a well-established point-wake model. We observe that for a finite wake charge, the monolayer hexagonal crystal undergoes a transition first to a bilayer hexagonal structure, unrealizable in harmonically confined reciprocal Yukawa systems, and subsequently to a bilayer square structure. Our theoretical results are confirmed by molecular dynamics simulations for experimentally relevant parameters, indicating the potential of their observation in state-of-the-art experiments with 2D complex plasmas.
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Affiliation(s)
- A V Zampetaki
- Max-Planck-Institut für Extraterrestrische Physik, 85741 Garching, Germany.,Institut für Theoretische Physik II, Weiche Materie, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - H Huang
- College of Science, Donghua University, 201620 Shanghai, People's Republic of China
| | - C-R Du
- College of Science, Donghua University, 201620 Shanghai, People's Republic of China
| | - H Löwen
- Institut für Theoretische Physik II, Weiche Materie, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - A V Ivlev
- Max-Planck-Institut für Extraterrestrische Physik, 85741 Garching, Germany
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Muangnapoh K, Avendaño C, Escobedo FA, Liddell Watson CM. Degenerate crystals from colloidal dimers under confinement. SOFT MATTER 2014; 10:9729-9738. [PMID: 25366128 DOI: 10.1039/c4sm01895h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Colloidal aperiodic phases (i.e., entropy stabilized degenerate crystals, DCs) are realized via self-assembly of hollow fluorescent silica dimers under wedge-cell confinement. The dimer building blocks approximate two tangent spheres and their arrangements are studied via laser scanning confocal microscopy. In the DCs, the individual lobes tile a lattice and five distinct DC arrangements with square, triangular or rectangular layer symmetry are determined as a function of confinement height. Moreover, Monte Carlo simulations are used to construct the phase diagram for DCs up to two layer confinements and to analyze structural order in detail. Just as for spheres, the DC structural transitions under confinement are attributed to the ability or frustration to accommodate an integral number of particle layers between hard walls. Unlike spheres, dimers can also experience transitions involving changes in orientation. DCs are among the unconventional structures (e.g., semi-regular tilings, quasicrystals, plastic crystals) expected to enhance the properties of photonic solids.
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Pandey R, Spannuth M, Conrad JC. Confocal imaging of confined quiescent and flowing colloid-polymer mixtures. J Vis Exp 2014:51461. [PMID: 24894062 PMCID: PMC4199466 DOI: 10.3791/51461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The behavior of confined colloidal suspensions with attractive interparticle interactions is critical to the rational design of materials for directed assembly(1-3), drug delivery(4), improved hydrocarbon recovery(5-7), and flowable electrodes for energy storage(8). Suspensions containing fluorescent colloids and non-adsorbing polymers are appealing model systems, as the ratio of the polymer radius of gyration to the particle radius and concentration of polymer control the range and strength of the interparticle attraction, respectively. By tuning the polymer properties and the volume fraction of the colloids, colloid fluids, fluids of clusters, gels, crystals, and glasses can be obtained(9). Confocal microscopy, a variant of fluorescence microscopy, allows an optically transparent and fluorescent sample to be imaged with high spatial and temporal resolution in three dimensions. In this technique, a small pinhole or slit blocks the emitted fluorescent light from regions of the sample that are outside the focal volume of the microscope optical system. As a result, only a thin section of the sample in the focal plane is imaged. This technique is particularly well suited to probe the structure and dynamics in dense colloidal suspensions at the single-particle scale: the particles are large enough to be resolved using visible light and diffuse slowly enough to be captured at typical scan speeds of commercial confocal systems(10). Improvements in scan speeds and analysis algorithms have also enabled quantitative confocal imaging of flowing suspensions(11-16,37). In this paper, we demonstrate confocal microscopy experiments to probe the confined phase behavior and flow properties of colloid-polymer mixtures. We first prepare colloid-polymer mixtures that are density- and refractive-index matched. Next, we report a standard protocol for imaging quiescent dense colloid-polymer mixtures under varying confinement in thin wedge-shaped cells. Finally, we demonstrate a protocol for imaging colloid-polymer mixtures during microchannel flow.
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Affiliation(s)
- Rahul Pandey
- Chemical and Biomolecular Engineering Department, University of Houston
| | - Melissa Spannuth
- Chemical and Biomolecular Engineering Department, University of Houston
| | - Jacinta C Conrad
- Chemical and Biomolecular Engineering Department, University of Houston;
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5
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Asbahi M, Mehraeen S, Lim KTP, Wang F, Cao J, Tan MC, Yang JKW. Template-induced structure transition in sub-10 nm self-assembling nanoparticles. NANO LETTERS 2014; 14:2642-2646. [PMID: 24702584 DOI: 10.1021/nl5004976] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on the directed self-assembly of sub-10 nm gold nanoparticles confined within a template comprising channels of gradually varying widths. When the colloidal lattice parameter is mismatched with the channel width, the nanoparticles rearrange and break their natural close-packed ordering, transiting through a range of structural configurations according to the constraints imposed by the channel. While much work has been done in assembling ordered configurations, studies of the transition regime between ordered states have been limited to microparticles under applied compression. Here, with coordinated experiments and Monte Carlo simulations we show that particles transit through a more diverse set of self-assembled configurations than observed for compressed systems. The new insight from this work could lead to the control and design of complex self-assembled patterns other than periodic arrays of ordered particles.
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Affiliation(s)
- Mohamed Asbahi
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) , Singapore 117602
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6
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Antlanger M, Doppelbauer G, Mazars M, Kahl G. Crystal phases of soft spheres systems in a slab geometry. J Chem Phys 2014; 140:044507. [PMID: 25669555 DOI: 10.1063/1.4862499] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We have identified the ground state configurations of soft particles (interacting via inverse power potentials) confined between two hard, impenetrable walls. To this end we have used a highly reliable optimization scheme at vanishing temperature while varying the wall separation over a representative range. Apart from the expected layered triangular and square structures (which are compatible with the three-dimensional bulk fcc lattice), we have identified a cascade of highly complex intermediate structures. Taking benefit of the general scaling properties of inverse power potentials, we could identify - for a given softness value - one single master curve which relates the energy to the wall separation, irrespective of the density of the system. Via extensive Monte Carlo simulations, we have performed closer investigations of these intermediate structures at finite temperature: we could provide evidence to which extent these particle arrangements remain stable over a relatively large temperature range.
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Affiliation(s)
- Moritz Antlanger
- Institut für Theoretische Physik and Center for Computational Materials Science (CMS), Technische Universität Wien, Wiedner Hauptstraße 8-10, A-1040 Wien, Austria
| | - Günther Doppelbauer
- Institut für Theoretische Physik and Center for Computational Materials Science (CMS), Technische Universität Wien, Wiedner Hauptstraße 8-10, A-1040 Wien, Austria
| | - Martial Mazars
- Laboratoire de Physique Théorique (UMR 8627), Université de Paris-Sud and CNRS, Bâtiment 210, F-91405 Orsay Cedex, France
| | - Gerhard Kahl
- Institut für Theoretische Physik and Center for Computational Materials Science (CMS), Technische Universität Wien, Wiedner Hauptstraße 8-10, A-1040 Wien, Austria
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7
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Hilhorst J, de Winter DAM, Wolters JR, Post JA, Petukhov AV. Defect engineering in sedimentary colloidal photonic crystals. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:10011-10018. [PMID: 23705909 DOI: 10.1021/la4011168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this paper, lithographic methods are successfully employed to create growth templates for colloidal self-assembly, enabling the inclusion of crystallographic defects at predetermined positions. It is shown that through smart template design stacking faults can be grown predictably into face centered cubic structures. More interestingly, by precise guiding of the stacking faults hollow intergrowth channels can be grown at predetermined lateral and vertical positions. The mechanisms involved in defect growth are promising for extension of this technique to more complex crystal structures, such as the diamond structure, as well as to more complex faults, including corners and t-junctions.
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Affiliation(s)
- Jan Hilhorst
- Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
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8
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Heitkam S, Drenckhan W, Fröhlich J. Packing spheres tightly: influence of mechanical stability on close-packed sphere structures. PHYSICAL REVIEW LETTERS 2012; 108:148302. [PMID: 22540826 DOI: 10.1103/physrevlett.108.148302] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Indexed: 05/31/2023]
Abstract
Many experiments and simulations of packings of monodisperse hard spheres report a dominance of the face-centered cubic structure in the hexagonally close-packed limit, even though it has no significant energetic or entropic gain over other close-packed configurations. Combining simulations and experiments, we demonstrate that a simple mechanical instability which occurs during the packing process may play an important role in selecting the face-centered cubic structure over other close-packed alternatives. Our argument is supported by detailed quantitative analyses of key configurations in sphere packings and highlights the importance of the packing dynamics. The proposed mechanism is elementary and should therefore play a role in a wide range of sphere systems.
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Affiliation(s)
- S Heitkam
- Laboratoire de Physique des Solides-UMR 8502, Université Paris Sud, 91405 Orsay, France
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9
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Colloidal Crystallization Between Two and Three Dimensions. ADVANCES IN CHEMICAL PHYSICS 2011. [DOI: 10.1002/9781118158715.ch3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
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10
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Galisteo-López JF, Ibisate M, Sapienza R, Froufe-Pérez LS, Blanco A, López C. Self-assembled photonic structures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:30-69. [PMID: 20878624 DOI: 10.1002/adma.201000356] [Citation(s) in RCA: 307] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Photonic crystals have proven their potential and are nowadays a familiar concept. They have been approached from many scientific and technological flanks. Among the many techniques devised to implement this technology self-assembly has always been one of great popularity surely due to its ease of access and the richness of results offered. Self-assembly is also probably the approach entailing more materials aspects owing to the fact that they lend themselves to be fabricated by a great many, very different methods on a vast variety of materials and to multiple purposes. To these well-known material systems a new sibling has been born (photonic glass) expanding the paradigm of optical materials inspired by solid state physics crystal concept. It is expected that they may become an important player in the near future not only because they complement the properties of photonic crystals but because they entice the researchers' curiosity. In this review a panorama is presented of the state of the art in this field with the view to serve a broad community concerned with materials aspects of photonic structures and more so those interested in self-assembly.
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Affiliation(s)
- Juan F Galisteo-López
- Instituto de Ciencia de Materiales de Madrid and Unidad Asociada CSIC-U Vigo, Calle Sor Juana Inés de la Cruz, 3; 28049 Madrid, Spain
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11
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Kahn M, Weis JJ, Kahl G. Ordered equilibrium structures of soft particles in thin layers. J Chem Phys 2010; 133:224504. [DOI: 10.1063/1.3509380] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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12
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Ramiro-Manzano F, Bonet E, Rodriguez I, Meseguer F. Colloidal crystal thin films grown into corrugated surface templates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:4559-4562. [PMID: 20184380 DOI: 10.1021/la904396m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The influence of patterned surfaces on the formation of one- and two-dimensional colloidal crystals is analyzed. We have used the corrugated surface of a digital versatile disc (DVD) for template surface processing. When the sphere diameter is on the order of the groove width of patterned substrates, a rich variety of particle decorations appear. However, if particle size is much larger than template patterns, large domains of particle ordering are formed.
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Affiliation(s)
- F Ramiro-Manzano
- Centro de Tecnologías Físicas, Unidad Asociada ICMM/CSIC-UPV, Universidad Politécnica de Valencia, Av. Los Naranjos s/n, 46022 Valencia, Spain
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13
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Arpin KA, Mihi A, Johnson HT, Baca AJ, Rogers JA, Lewis JA, Braun PV. Multidimensional architectures for functional optical devices. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:1084-1101. [PMID: 20401933 DOI: 10.1002/adma.200904096] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Materials exhibiting multidimensional structure with characteristic lengths ranging from the nanometer to the micrometer scale have extraordinary potential for emerging optical applications based on the regulation of light-matter interactions via the mesoscale organization of matter. As the structural dimensionality increases, the opportunities for controlling light-matter interactions become increasingly diverse and powerful. Recent advances in multidimensional structures have been demonstrated that serve as the basis for three-dimensional photonic-bandgap materials, metamaterials, optical cloaks, highly efficient low-cost solar cells, and chemical and biological sensors. In this Review, the state-of-the-art design and fabrication of multidimensional architectures for functional optical devices are covered and the next steps for this important field are described.
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Affiliation(s)
- Kevin A Arpin
- Frederick Seitz Materials Research Laboratory 104 South Goodwin Ave Urbana, IL 61801, USA
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14
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Löwen H. Twenty years of confined colloids: from confinement-induced freezing to giant breathing. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:474203. [PMID: 21832482 DOI: 10.1088/0953-8984/21/47/474203] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The physics of colloidal suspensions confined in slits and cavities has significantly advanced during the last twenty years. In particular, freezing transitions in confinement have been addressed by theory and simulations and experimental realizations were proposed to confine colloidal particles to two dimensions. After reviewing this progress, we discuss the generalization to time-dependent confinement which leads to nonequilibrium situations. This is elaborated further for unstable situations where the particles can leave the confinement. In particular, the completely overdamped Brownian motion of a colloidal particle in a time-dependent harmonic trap is considered. The analytically soluble model of a time-dependent quadratic potential is used to extract the dynamical properties of the potential if the potential undergoes periodic switching from a confining harmonic potential to an unstable one. The amplitudes of the oscillating particle response can strongly grow in time, which we refer to as 'giant breathing'. This giant breathing process occurs also in anharmonic potentials and is verifiable in real-space experiments of colloids in laser-optical fields.
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Affiliation(s)
- H Löwen
- Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, D-40225 Düsseldorf, Germany
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Fontecha AB, Palberg T, Schöpe HJ. Construction and stability of a close-packed structure observed in thin colloidal crystals. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 76:050402. [PMID: 18233615 DOI: 10.1103/physreve.76.050402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Indexed: 05/25/2023]
Abstract
We have characterized a close-packed structure of confined charged colloidal spheres, which has been recently discovered. Using different microscopy experiments, the vertically arranged hexagonal planes of n - hcp perpendicular are found to continuously evolve from the horizontally oriented stacks of n hexagonal planes (nDelta) following the maximum packing criterion, but discontinuously transform to a stack of n+1 square planes [(n+1)[SHAPE OF A SQUARE]]. Large mechanically stable domains with threefold twin structures are regularly observed in the suspended state at packing fractions between 0.4 and 0.58.
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Affiliation(s)
- Ana Barreira Fontecha
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, D-55128 Mainz, Germany
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17
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Ramiro-Manzano F, Bonet E, Rodriguez I, Meseguer F. Layering transitions in confined colloidal crystals: the hcp-like phase. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 76:050401. [PMID: 18233614 DOI: 10.1103/physreve.76.050401] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 07/31/2007] [Indexed: 05/25/2023]
Abstract
This paper investigates the sequence of morphological transitions in a nearly hard sphere arrangement confined in a wedge cell. A model that shows smooth transitions between the different particle orderings for a small number of layers is proposed. In this model, both the buckling and the (100) hexagonal close packed (hcp) phases are particular cases of a much more general particle arrangement tendency that we call hcp-like ordering. This phase, which does not correspond to any known close packed ordering, is able to adopt packing arrangements commensurate with the cell thickness. More striking, the hcp-like phase adapts itself to the progressive changes of the cell thickness by a smooth change in the interlayer spacing. We present hcp-like orderings up to six layers and a complete sequence of transformations between two and four layers. Finally, a packing model of the transition from two to three layers is also presented.
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Affiliation(s)
- F Ramiro-Manzano
- Centro Tecnológico de Ondas-Unidad Asociada CSIC-ICMM/UPV, Universidad Politécnica de Valencia, Avenida Los Naranjos, 46022 Valencia, Spain
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18
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Klokkenburg M, Erné BH, Wiedenmann A, Petukhov AV, Philipse AP. Dipolar structures in magnetite ferrofluids studied with small-angle neutron scattering with and without applied magnetic field. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 75:051408. [PMID: 17677066 DOI: 10.1103/physreve.75.051408] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 03/15/2007] [Indexed: 05/16/2023]
Abstract
Field-induced structure formation in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment was studied with small-angle neutron scattering (SANS) as a function of the magnetic interactions. The interactions were tuned by adjusting the size of the well-defined, single-magnetic-domain magnetite (Fe3O4) particles and by applying an external magnetic field. For decreasing particle dipole moments, the data show a progressive distortion of the hexagonal symmetry, resulting from the formation of magnetic sheets. The SANS data show qualitative agreement with recent cryogenic transmission electron microscopy results obtained in 2D [Klokkenburg, Phys. Rev. Lett. 97, 185702 (2006)] on the same ferrofluids.
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Affiliation(s)
- M Klokkenburg
- Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, Utrecht University, Padualaan 8, Utrecht, The Netherlands.
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Klokkenburg M, Erné BH, Meeldijk JD, Wiedenmann A, Petukhov AV, Dullens RPA, Philipse AP. In situ imaging of field-induced hexagonal columns in magnetite ferrofluids. PHYSICAL REVIEW LETTERS 2006; 97:185702. [PMID: 17155554 DOI: 10.1103/physrevlett.97.185702] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Indexed: 05/04/2023]
Abstract
Field-induced structures in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment are analyzed on a single-particle level by in situ cryogenic transmission electron microscopy (2D). The field-induced columnar phase locally exhibits hexagonal symmetry and confirms the structures observed in simulations for ferromagnetic dipolar fluids in 2D. The columns are distorted by lens-shaped voids, due to the weak interchain attraction relative to field-directed dipole-dipole attraction. Both dipolar coupling and the dipole concentration determine the dimensions and the spatial arrangement of the columns. Their regular spacing manifests long-range end-pole repulsions that eventually dominate the fluctuation-induced attractions between dipole chains that initiate the columnar transition.
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Affiliation(s)
- Mark Klokkenburg
- Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
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