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Sasai R, Fujimura T, Sato H, Nii E, Sugata M, Nakayashiki Y, Hoashi H, Moriyoshi C, Oishi E, Fujii Y, Kawaguchi S, Tanaka H. Origin of Selective Nitrate Removal by Ni 2+–Al 3+ Layered Double Hydroxides in Aqueous Media and Its Application Potential in Seawater Purification. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2022. [DOI: 10.1246/bcsj.20220032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Ryo Sasai
- Chemistry Course, Major in Science of Environmental Systems, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
| | - Takuya Fujimura
- Chemistry Course, Major in Science of Environmental Systems, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
| | - Hiroaki Sato
- Chemistry Course, Major in Science of Environmental Systems, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
| | - Eisaku Nii
- Chemistry Course, Major in Science of Environmental Systems, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
| | - Mako Sugata
- Chemistry Course, Major in Science of Environmental Systems, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
| | - Yuto Nakayashiki
- Chemistry Course, Major in Science of Environmental Systems, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
| | - Hirokazu Hoashi
- Department of Physical Science, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
| | - Chikako Moriyoshi
- Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
| | - Eiichi Oishi
- Department of Physical Sciences, College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu 525-8577, Japan
| | - Yasuhiro Fujii
- Department of Physical Sciences, College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu 525-8577, Japan
| | - Shogo Kawaguchi
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Hiroshi Tanaka
- Physics and Applied Physics Course, Major in Science and Engineering, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue 690-8504, Japan
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2
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Virovets AV, Peresypkina E, Scheer M. Structural Chemistry of Giant Metal Based Supramolecules. Chem Rev 2021; 121:14485-14554. [PMID: 34705437 DOI: 10.1021/acs.chemrev.1c00503] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The review presents a bird-eye view on the state of research in the field of giant nonbiological discrete metal complexes and ions of nanometer size, which are structurally characterized by means of single-crystal X-ray diffraction, using the crystal structure as a common key feature. The discussion is focused on the main structural features of the metal clusters, the clusters containing compact metal oxide/hydroxide/chalcogenide core, ligand-based metal-organic cages, and supramolecules as well as on the aspects related to the packing of the molecules or ions in the crystal and the methodological aspects of the single-crystal neutron and X-ray diffraction of these compounds.
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Affiliation(s)
- Alexander V Virovets
- Institute of Inorganic Chemistry, University of Regensburg, Universitaetsstr. 31, 93053 Regensburg, Germany
| | - Eugenia Peresypkina
- Institute of Inorganic Chemistry, University of Regensburg, Universitaetsstr. 31, 93053 Regensburg, Germany
| | - Manfred Scheer
- Institute of Inorganic Chemistry, University of Regensburg, Universitaetsstr. 31, 93053 Regensburg, Germany
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Sasai R, Sato H, Sugata M, Fujimura T, Ishihara S, Deguchi K, Ohki S, Tansho M, Shimizu T, Oita N, Numoto M, Fujii Y, Kawaguchi S, Matsuoka Y, Hagura K, Abe T, Moriyoshi C. Why Do Carbonate Anions Have Extremely High Stability in the Interlayer Space of Layered Double Hydroxides? Case Study of Layered Double Hydroxide Consisting of Mg and Al (Mg/Al = 2). Inorg Chem 2019; 58:10928-10935. [DOI: 10.1021/acs.inorgchem.9b01365] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ryo Sasai
- Department of Materials Chemistry, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue, Shimane 690-8504, Japan
| | - Hiroaki Sato
- Department of Materials Chemistry, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue, Shimane 690-8504, Japan
| | - Mako Sugata
- Department of Materials Chemistry, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue, Shimane 690-8504, Japan
| | - Takuya Fujimura
- Department of Materials Chemistry, Graduate School of Natural Science and Technology, Shimane University, 1060 Nishi-Kawatsu-cho, Matsue, Shimane 690-8504, Japan
| | - Shinsuke Ishihara
- World Premier International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan
| | - Kenzo Deguchi
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Shinobu Ohki
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Masataka Tansho
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Tadashi Shimizu
- High Field NMR Group, National Institute for Materials Science (NIMS), 3-13 Sakura, Tsukuba, Ibaraki 305-0003, Japan
| | - Naoto Oita
- Department of Physics and Mathematics, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
| | - Mako Numoto
- Department of Physical Sciences, College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Yasuhiro Fujii
- Department of Physics and Mathematics, College of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
- Department of Physical Sciences, College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Shogo Kawaguchi
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-Cho, Sayo-Gun, Hyogo 679-5198, Japan
| | - Yoshiki Matsuoka
- Department of Physical Science, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Koki Hagura
- Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Sayo-Cho, Sayo-Gun, Hyogo 679-5198, Japan
- Department of Physical Science, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Tomohiro Abe
- Department of Physical Science, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Chikako Moriyoshi
- Department of Physical Science, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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4
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Zhang L, Stephens AJ, Nussbaumer AL, Lemonnier JF, Jurček P, Vitorica-Yrezabal IJ, Leigh DA. Stereoselective synthesis of a composite knot with nine crossings. Nat Chem 2018; 10:1083-1088. [DOI: 10.1038/s41557-018-0124-6] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 07/20/2018] [Indexed: 01/10/2023]
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Antoinette MM, Israel S, Sathya G, Amali AJ, Berchmans JL, Sujatha K, Anzline C, Devi RN. Experimental charge density distribution and its correlation to structural and optical properties of Sm 3+ doped Nd 2 O 3 nanophosphors. J RARE EARTH 2017. [DOI: 10.1016/j.jre.2017.04.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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6
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Electrochemical and structural study on LiMn0.8Fe0.2PO4 and Mn0.8Fe0.2PO4 battery cathodes: diffusion limited lithium transport. J Solid State Electrochem 2017. [DOI: 10.1007/s10008-017-3636-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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7
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Self-assembly of tetravalent Goldberg polyhedra from 144 small components. Nature 2016; 540:563-566. [DOI: 10.1038/nature20771] [Citation(s) in RCA: 389] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 10/25/2016] [Indexed: 12/18/2022]
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9
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Stash AI, Tsirelson VG. DevelopingWinXPRO: a software for determination of the multipole-model-based properties of crystals. J Appl Crystallogr 2014. [DOI: 10.1107/s1600576714021566] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The new release of the computer program packageWinXPRO v.3xfor determination of the crystal properties from parameters of the multipole-modeled experimental electron density and anharmonic atomic displacement coefficients is described. The set of properties is significantly extended by using the density functional and information theories. In addition, a built-in multi-functional viewer and programs to display the output data, including the mapping of the chosen functional bonding descriptors onto surfaces of the other properties, are included.
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Jørgensen MRV, Hathwar VR, Bindzus N, Wahlberg N, Chen YS, Overgaard J, Iversen BB. Contemporary X-ray electron-density studies using synchrotron radiation. IUCRJ 2014; 1:267-80. [PMID: 25295169 PMCID: PMC4174870 DOI: 10.1107/s2052252514018570] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 08/14/2014] [Indexed: 06/02/2023]
Abstract
Synchrotron radiation has many compelling advantages over conventional radiation sources in the measurement of accurate Bragg diffraction data. The variable photon energy and much higher flux may help to minimize critical systematic effects such as absorption, extinction and anomalous scattering. Based on a survey of selected published results from the last decade, the benefits of using synchrotron radiation in the determination of X-ray electron densities are discussed, and possible future directions of this field are examined.
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Affiliation(s)
- Mads R. V. Jørgensen
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus C, DK-8000, Denmark
| | - Venkatesha R. Hathwar
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus C, DK-8000, Denmark
| | - Niels Bindzus
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus C, DK-8000, Denmark
| | - Nanna Wahlberg
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus C, DK-8000, Denmark
| | - Yu-Sheng Chen
- ChemMatCARS, Advanced Photon Source, University of Chicago, USA
| | - Jacob Overgaard
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus C, DK-8000, Denmark
| | - Bo B. Iversen
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, Langelandsgade 140, Aarhus C, DK-8000, Denmark
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11
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Carrington EJ, Vitórica-Yrezábal IJ, Brammer L. Crystallographic studies of gas sorption in metal-organic frameworks. ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2014; 70:404-22. [PMID: 24892587 PMCID: PMC4045145 DOI: 10.1107/s2052520614009834] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 05/01/2014] [Indexed: 05/25/2023]
Abstract
Metal-organic frameworks (MOFs) are a class of porous crystalline materials of modular design. One of the primary applications of these materials is in the adsorption and separation of gases, with potential benefits to the energy, transport and medical sectors. In situ crystallography of MOFs under gas atmospheres has enabled the behaviour of the frameworks under gas loading to be investigated and has established the precise location of adsorbed gas molecules in a significant number of MOFs. This article reviews progress in such crystallographic studies, which has taken place over the past decade, but has its origins in earlier studies of zeolites, clathrates etc. The review considers studies by single-crystal or powder diffraction using either X-rays or neutrons. Features of MOFs that strongly affect gas sorption behaviour are discussed in the context of in situ crystallographic studies, specifically framework flexibility, and the presence of (organic) functional groups and unsaturated (open) metal sites within pores that can form specific interactions with gas molecules.
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Affiliation(s)
- Elliot J. Carrington
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, England
| | | | - Lee Brammer
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, England
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12
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Kim Y, Kim J, Fujiwara A, Taniguchi H, Kim S, Tanaka H, Sugimoto K, Kato K, Itoh M, Hosono H, Takata M. Hierarchical dielectric orders in layered ferroelectrics Bi2SiO5. IUCRJ 2014; 1:160-164. [PMID: 25075334 PMCID: PMC4086432 DOI: 10.1107/s2052252514008008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 04/10/2014] [Indexed: 06/03/2023]
Abstract
Electric dipole engineering is now an emerging technology for high electron-mobility transistors, ferroelectric random access memory and multiferroic devices etc. Although various studies to provide insight into dipole moment behaviour, such as phase transition, order and disorder states, have been reported, macroscopic spontaneous polarization has been mainly discussed so far. Here, visualization of the electric dipole arrangement in layered ferroelectrics Bi2SiO5 by means of combined analysis of maximum entropy charge density and electrostatic potential distribution analysis based on synchrotron radiation X-ray powder diffraction data is reported. It was found that the hierarchical dipole orders, the weak-ferroelectric and ferroelectric configurations, were observed in the Bi2O2 and the SiO3 layers, respectively, and the ferrielectric configuration was realised by the interlayer interaction. This discovery provides a new method to visualize the local polarization in ferroelectric materials.
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Affiliation(s)
- Younghun Kim
- Department of Advanced Materials Science, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan
- RIKEN SPring-8 Center, Kouto, Sayo-cho, Hyogo 679-5148, Japan
| | - Jungeun Kim
- RIKEN SPring-8 Center, Kouto, Sayo-cho, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, Kouto, Sayo-cho, Hyogo 679-5148, Japan
| | - Akihiko Fujiwara
- Japan Synchrotron Radiation Research Institute, Kouto, Sayo-cho, Hyogo 679-5148, Japan
| | - Hiroki Taniguchi
- Department of Physics, Nagoya University, Furo-cho, Nagoya 464-8602, Japan
| | - Sungwng Kim
- Department of Energy Science, Sungkyunkwan University, Jangan-Gu, Suwon 440-746, South Korea
| | - Hiroshi Tanaka
- Department of Materials Science, Shimane University, 1060 Nishi-kawatsu-cho, Matsue, Shimane 690-8504, Japan
| | - Kunihisa Sugimoto
- RIKEN SPring-8 Center, Kouto, Sayo-cho, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, Kouto, Sayo-cho, Hyogo 679-5148, Japan
| | - Kenichi Kato
- RIKEN SPring-8 Center, Kouto, Sayo-cho, Hyogo 679-5148, Japan
| | - Mitsuru Itoh
- Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Hideo Hosono
- Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan
- Frontier Research Center, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Masaki Takata
- Department of Advanced Materials Science, The University of Tokyo, Kashiwa, Chiba 277-8561, Japan
- RIKEN SPring-8 Center, Kouto, Sayo-cho, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, Kouto, Sayo-cho, Hyogo 679-5148, Japan
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Sasai R, Matsuoka Y, Sato H, Moriyoshi C, Kuroiwa Y. Abnormally Large Thermal Vibration of Chloride Anions Incorporated in Layered Double Hydroxide Consisting of Mg and Al (Mg/Al = 2). CHEM LETT 2013. [DOI: 10.1246/cl.130576] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Ryo Sasai
- Interdisciplinary Graduate School of Science and Engineering, Shimane University
| | | | - Hiroaki Sato
- Interdisciplinary Graduate School of Science and Engineering, Shimane University
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Grabowsky S, Jayatilaka D, Fink RF, Schirmeister T, Engels B. Can Experimental Electron-Density Studies be Used as a Tool to Predict Biologically Relevant Properties of Low-Molecular Weight Enzyme Ligands? Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201200518] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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15
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Prathapa SJ, Mondal S, van Smaalen S. Electron densities by the maximum entropy method (MEM) for various types of prior densities: a case study on three amino acids and a tripeptide. ACTA CRYSTALLOGRAPHICA SECTION B STRUCTURAL SCIENCE CRYSTAL ENGINEERING AND MATERIALS 2013. [DOI: 10.1107/s0108768113004874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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16
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Protein encapsulation within synthetic molecular hosts. Nat Commun 2012; 3:1093. [DOI: 10.1038/ncomms2093] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 08/29/2012] [Indexed: 11/09/2022] Open
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Rudolf M, Wolfrum S, Guldi DM, Feng L, Tsuchiya T, Akasaka T, Echegoyen L. Endohedral Metallofullerenes-Filled Fullerene Derivatives towards Multifunctional Reaction Center Mimics. Chemistry 2012; 18:5136-48. [DOI: 10.1002/chem.201102844] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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18
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Li L, Wölfel A, Schönleber A, Mondal S, Schreurs AMM, Kroon-Batenburg LMJ, van Smaalen S. Modulated anharmonic ADPs are intrinsic to aperiodic crystals: a case study on incommensurate Rb2ZnCl4. ACTA CRYSTALLOGRAPHICA. SECTION B, STRUCTURAL SCIENCE 2011; 67:205-17. [PMID: 21586828 PMCID: PMC3098556 DOI: 10.1107/s0108768111013814] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 04/12/2011] [Indexed: 11/10/2022]
Abstract
A combination of structure refinements, analysis of the superspace MEM density and interpretation of difference-Fourier maps has been used to characterize the incommensurate modulation of rubidium tetrachlorozincate, Rb(2)ZnCl(4), at a temperature of T = 196 K, close to the lock-in transition at T(lock-in) = 192 K. The modulation is found to consist of a combination of displacement modulation functions, modulated atomic displacement parameters (ADPs) and modulated third-order anharmonic ADPs. Up to fifth-order Fourier coefficients could be refined against diffraction data containing up to fifth-order satellite reflections. The center-of-charge of the atomic basins of the MEM density and the displacive modulation functions of the structure model provide equivalent descriptions of the displacive modulation. Modulations of the ADPs and anharmonic ADPs are visible in the MEM density, but extracting quantitative information about these modulations appears to be difficult. In the structure refinements the modulation parameters of the ADPs form a dependent set, and ad hoc restrictions had to be introduced in the refinements. It is suggested that modulated harmonic ADPs and modulated third-order anharmonic ADPs form an intrinsic part, however small, of incommensurately modulated structures in general. Refinements of alternate models with and without parameters for modulated ADPs lead to significant differences between the parameters of the displacement modulation in these two types of models, thus showing the modulation of ADPs to be important for a correct description of the displacive modulation. The resulting functions do not provide evidence for an interpretation of the modulation by a soliton model.
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Affiliation(s)
- Liang Li
- Laboratory of Crystallography, University of Bayreuth, Germany
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Samy A, Dinnebier RE, van Smaalen S, Jansen M. Maximum entropy method and charge flipping, a powerful combination to visualize the true nature of structural disorder from in situ X-ray powder diffraction data. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 2010; 66:184-95. [PMID: 20305352 DOI: 10.1107/s0108768109052616] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Accepted: 12/07/2009] [Indexed: 11/10/2022]
Abstract
In a systematic approach, the ability of the Maximum Entropy Method (MEM) to reconstruct the most probable electron density of highly disordered crystal structures from X-ray powder diffraction data was evaluated. As a case study, the ambient temperature crystal structures of disordered alpha-Rb(2)[C(2)O(4)] and alpha-Rb(2)[CO(3)] and ordered delta-K(2)[C(2)O(4)] were investigated in detail with the aim of revealing the ;true' nature of the apparent disorder. Different combinations of F (based on phased structure factors) and G constraints (based on structure-factor amplitudes) from different sources were applied in MEM calculations. In particular, a new combination of the MEM with the recently developed charge-flipping algorithm with histogram matching for powder diffraction data (pCF) was successfully introduced to avoid the inevitable bias of the phases of the structure-factor amplitudes by the Rietveld model. Completely ab initio electron-density distributions have been obtained with the MEM applied to a combination of structure-factor amplitudes from Le Bail fits with phases derived from pCF. All features of the crystal structures, in particular the disorder of the oxalate and carbonate anions, and the displacements of the cations, are clearly obtained. This approach bears the potential of a fast method of electron-density determination, even for highly disordered materials. All the MEM maps obtained in this work were compared with the MEM map derived from the best Rietveld refined model. In general, the phased observed structure factors obtained from Rietveld refinement (applying F and G constraints) were found to give the closest description of the experimental data and thus lead to the most accurate image of the actual disorder.
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Affiliation(s)
- Ali Samy
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
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20
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Li L, Schönleber A, van Smaalen S. Modulation functions of incommensurately modulated Cr2P2O7 studied by the maximum entropy method (MEM). ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 2010; 66:130-40. [PMID: 20305346 DOI: 10.1107/s0108768110003393] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Accepted: 01/27/2010] [Indexed: 11/10/2022]
Abstract
The maximum entropy method (MEM) has been used to determine electron density in superspace of incommensurately modulated chromium pyrophosphate from X-ray diffraction data measured by Palatinus et al. [(2006), Acta Cryst. B62, 556-566]. Chromium pyrophosphate, Cr(2)P(2)O(7), contains ordered regions (83% of the volume) and regions with disorder. Analysis of the MEM density has allowed the determination of the displacive modulation functions within ordered regions. The disordered regions can be described as the alternate occupation of two conformations of the pyrophosphate group and two positions of the chromium atom, with occupational probabilities that depend continuously on the phase of modulation t. A structure model based on the interpretation of the MEM density provides a fit to the diffraction data of the same quality as the model given by Palatinus et al. (2006). The failure to find a model that better fits the data is attributed to the intrinsic inaccuracy of approximately 0.01 A for positions derived from the MEM and to the difficulties in constructing an appropriate model for the anharmonic ADPs and their modulation functions from electron densities.
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Affiliation(s)
- Liang Li
- Laboratory of Crystallography, University of Bayreuth, 95440 Bayreuth, Germany
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Akasaka T, Kono T, Takematsu Y, Nikawa H, Nakahodo T, Wakahara T, Ishitsuka MO, Tsuchiya T, Maeda Y, Liu MTH, Yoza K, Kato T, Yamamoto K, Mizorogi N, Slanina Z, Nagase S. Does Gd@C82 have an anomalous endohedral structure? Synthesis and single crystal X-ray structure of the carbene adduct. J Am Chem Soc 2008; 130:12840-1. [PMID: 18778060 DOI: 10.1021/ja802156n] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report here the results on single crystal X-ray crystallographic analysis of the Gd@C82 carbene adduct (Gd@C82(Ad), Ad = adamantylidene). The Gd atom in Gd@C82(Ad) is located at an off-centered position near a hexagonal ring in the C2v-C82 cage, as found for M@C82 (M = Sc and La) and La@C82(Ad). Theoretical calculation also confirms the position of the Gd atom in the X-ray crystal structure.
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Affiliation(s)
- Takeshi Akasaka
- Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan.
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