Home  About us  Contact
 

Inorganic Crystals (inorganic + crystal)

Distribution by Scientific Domains
Polymers and Materials Science57%
Chemistry42%

Terms modified by Inorganic Crystals

  • inorganic crystal structure database
    		•

    Selected Abstracts

    Cover Picture: Hierarchically Organized Superstructure Emerging from the Exquisite Association of Inorganic Crystals, Organic Polymers, and Dyes: A Model Approach Towards Suprabiomineral Materials (Adv. Funct.

    ADVANCED FUNCTIONAL MATERIALS, Issue 9 2005
    Mater.
    Abstract Suprabiomineral materials possessing hierarchically organized superstructures are investigated by Imai and Oaki on p.,1407. Inorganic crystals, organic polymers, and functional dyes have assembled via a simple biomimetic route into a superstructure that contains six different tiers, from the macroscale to the nanoscale. The hierarchy originates from the strong interaction between crystals and polymers and the diffusion-controlled conditions. The versatile role of the polymer is found to be essential for the construction of a superstructure. This approach promises to generate novel types of functional materials with controllable structures and properties. We report a novel hierarchically organized superstructure emerging from an exquisite association of inorganic crystals, organic polymers, and dyes. The resultant K2SO4/poly(acrylic acid) composite includes five different tiers from the nanoscopic to the macroscopic. An additional new tier leading to functionality is formed by the incorporation of organic dyes that are organized in a nanospace. The emergent superstructure and properties are designed through changes in polymer concentration. The multiple roles of the polymer realize the generation of the architecture at each size scale. This model approach should be widely applicable to other systems, allowing for the preparation of innovative materials by an appropriate combination of crystals, polymers, and functional molecules. [source]

    Vibrational and optical properties of a one-dimensional organic,inorganic crystal [C6H14N]PbI3

    JOURNAL OF RAMAN SPECTROSCOPY, Issue 7 2008
    S. Elleuch
    Abstract Self-assembled organic,inorganic [C6H14N]PbI3 crystals were synthesized. The crystal structure consists of one-dimensional semiconductor chains formed by infinite PbI6 face-sharing octahedra aligned along the a -axis. The organic cations are linked to the inorganic chains by NH· · ·I hydrogen bonds and act as insulator barriers. The vibrational properties of [C6H14N]PbI3 were studied using polarized Raman scattering and infrared (IR) absorption. The observed Raman and IR spectral features were identified by comparison with the vibrational properties of homologous compounds and with the vibrational wavenumbers calculated using the ab initio PM3 method. Moreover, the photoluminescence and diffuse reflectance of [C6H14N]PbI3 single crystals, along with the UV-Vis absorption of spin- coated films, were measured. A strong green-blue luminescence due to radiative recombinations of 1D excitons is observed. The Stokes shift is estimated at 70 meV. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Benzylamines as Versatile Agents for the One-Pot Synthesis and Highly Ordered Stacking of Anatase Nanoplatelets

    EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2008
    Georg Garnweitner
    Abstract The simple reaction of titanium isopropoxide in benzylamine is shown to lead to remarkably complex, highly ordered hybrid structures. These structures consist of anatase nanoplatelets that were stacked in a lamellar fashion with a small organic layer in between. By careful characterization of these structures, we show that indeed solely the benzylamine solvent is present in the organic moiety between the nanocrystals, which thereby provides both shape control and alignment of the inorganic crystals. The solvent also plays a central role during the anatase formation itself; hence, it enacts control on the forming materials on a multitude of levels.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]

    Cover Picture: Hierarchically Organized Superstructure Emerging from the Exquisite Association of Inorganic Crystals, Organic Polymers, and Dyes: A Model Approach Towards Suprabiomineral Materials (Adv. Funct.

    ADVANCED FUNCTIONAL MATERIALS, Issue 9 2005
    Mater.
    Abstract Suprabiomineral materials possessing hierarchically organized superstructures are investigated by Imai and Oaki on p.,1407. Inorganic crystals, organic polymers, and functional dyes have assembled via a simple biomimetic route into a superstructure that contains six different tiers, from the macroscale to the nanoscale. The hierarchy originates from the strong interaction between crystals and polymers and the diffusion-controlled conditions. The versatile role of the polymer is found to be essential for the construction of a superstructure. This approach promises to generate novel types of functional materials with controllable structures and properties. We report a novel hierarchically organized superstructure emerging from an exquisite association of inorganic crystals, organic polymers, and dyes. The resultant K2SO4/poly(acrylic acid) composite includes five different tiers from the nanoscopic to the macroscopic. An additional new tier leading to functionality is formed by the incorporation of organic dyes that are organized in a nanospace. The emergent superstructure and properties are designed through changes in polymer concentration. The multiple roles of the polymer realize the generation of the architecture at each size scale. This model approach should be widely applicable to other systems, allowing for the preparation of innovative materials by an appropriate combination of crystals, polymers, and functional molecules. [source]

    Polymer-Controlled Crystallization of Unique Mineral Superstructures

    ADVANCED MATERIALS, Issue 4 2010
    Shao-Feng Chen
    Abstract The origin of complex superstructures of biomaterials in biological systems and the amazing self-assembly mechanisms of their emergence have attracted a great deal of attention recently. Mimicking nature, diverse kinds of hydrophilic polymers with different functionalities and organic insoluble matrices have been designed for the morphogenesis of inorganic crystals. In this Research News, emerging new strategies for morphogenesis and controlled crystal growth of minerals, that is, selective adsorption and mesoscale transformation for highly ordered superstructures, the combination of a synthetic hydrophilic polymer with an insoluble matrix, a substrate, or the air/solution interface, and controlled crystallization in a mixed solvent are highlighted. It is shown that these new strategies can be even further extended to morphogenesis and controlled crystallization of diverse inorganic or inorganic,organic hybrid materials with structural complexity, structural specialties, and improved functionalities. [source]

    Growth and aggregation of vaterite in seeded-batch experiments

    AICHE JOURNAL, Issue 11 2004
    Jens-P.
    Abstract Seeded-batch crystallization experiments allowing study of the growth and aggregation of the Vaterite modification of calcium carbonate are reported. Results are reported for initial relative supersaturation (, = S , 1) values in the range 1.66 to 6.70, stirrer speeds in the range 400 and 1200 rpm, and at temperatures of 25 and 40°C. It is found that in all cases the linear rate of growth of the particles is size independent and depends on relative supersaturation squared. The aggregation process is apparently size independent with a rate constant that is directly proportional to the instantaneous growth rate and decreases with increasing stirrer speed. The behavior of the aggregation rate constant is very well described by the model recently proposed by Liew et al., in which the efficiency of the aggregation process is predicted to depend only on the dimensionless strength of the particles and the nature of the flow field. It is concluded that Vaterite forms aggregates with crystalline bridges having an effective strength of approximately 25% of that of calcite or calcium oxalate monohydrate. The fitted parameter L,*/M50 takes on a value of 0.18 ± 0.02. The kinetics and associated model are capable of describing the evolving particle size distributions very well. Finally, a hypothesis is advanced to describe the aggregation of small inorganic crystals in supersaturated solutions. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2772,2782, 2004 [source]