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Limin Zheng - One of the best experts on this subject based on the ideXlab platform.

  • Proton conductive metal phosphonate frameworks
    Coordination Chemistry Reviews, 2017
    Co-Authors: George K. H. Shimizu, Limin Zheng
    Abstract:

    Abstract This review covers basic design principles and offers a cross-section of the current status of phosphonate MOFs as proton conductors. Metal phosphonates are often sustained by strong bonds that render them very stable materials. The phosphonate group can also coordinate as a protonated species. These factors, coupled with the inherent structural versatility intrinsic to any metal organic framework family, are the foundation of their interest as proton conducting materials. This review summarizes the recent progress in this topical field as well as some of the existing challenges for further development. The present state of application of the materials is still largely in the academic domain but increasingly, new structures with the necessary proton conducting ability and stability to merit further development as membranes are being reported. The review concludes with a discussion of future challenges for development of this promising field.

  • magnetic materials based on 3d metal phosphonates
    Coordination Chemistry Reviews, 2016
    Co-Authors: Limin Zheng
    Abstract:

    Abstract Metal phosphonate chemistry has witnessed a rapid development during the past two decades. Numerous compounds have been synthesized which show new architectures and interesting physical or chemical properties. In this article, we focus on the 3d transition metal phosphonate clusters with single molecule magnet behavior; chain compounds with single chain magnet behavior; and layer or three-dimensional compounds with ferromagnetism, ferrimagnetism, canted antiferromagnetism, and metamagnetism. Finally, magnetic 3d metal phosphonates with multifunctions are also discussed.

  • M2(pbtcH)(phen)2(H2O)2 [M(II) = Co, Ni]: Mixed-ligated metal phosphonates based on 5-phosphonatophenyl-1,2,4-tricarboxylic acid showing double chain structures
    Chinese Chemical Letters, 2014
    Co-Authors: Tao Zheng, Limin Zheng
    Abstract:

    Abstract Two new mixed-ligated metal phosphonates, M 2 (pbtcH)(phen) 2 (H 2 O) 2 [M(II) = Co ( 1 ), Ni ( 2 )] (pbtcH 5  = 5-phosphonatophenyl-1,2,4-tricarboxylic acid, phen = 1,10-phenanthroline), have been synthesized and characterized. Both show one-dimensional double chain structures, where the M(phen)(H 2 O) moieties are chelated and bridged by pbtcH 4− through the carboxylate and phosphonate oxygen atoms. The chains are connected by hydrogen bonding interactions and π – π stacking, forming a three-dimensional supramolecular structure. The IR and magnetic properties of the two compounds are also investigated.

  • m2 pbtch phen 2 h2o 2 m ii co ni mixed ligated metal phosphonates based on 5 phosphonatophenyl 1 2 4 tricarboxylic acid showing double chain structures
    Chinese Chemical Letters, 2014
    Co-Authors: Tao Zheng, Limin Zheng
    Abstract:

    Abstract Two new mixed-ligated metal phosphonates, M 2 (pbtcH)(phen) 2 (H 2 O) 2 [M(II) = Co ( 1 ), Ni ( 2 )] (pbtcH 5  = 5-phosphonatophenyl-1,2,4-tricarboxylic acid, phen = 1,10-phenanthroline), have been synthesized and characterized. Both show one-dimensional double chain structures, where the M(phen)(H 2 O) moieties are chelated and bridged by pbtcH 4− through the carboxylate and phosphonate oxygen atoms. The chains are connected by hydrogen bonding interactions and π – π stacking, forming a three-dimensional supramolecular structure. The IR and magnetic properties of the two compounds are also investigated.

  • Polar metal phosphonate containing unusual μ4-OH bridged double chains showing canted antiferromagnetism with large coercivity
    Chemical Communications, 2014
    Co-Authors: Xiao Jing Yang, Norihisa Hoshino, Tomoyuki Akutagawa, Limin Zheng
    Abstract:

    The first examples of metal phosphonates based on an asymmetrical 2-(phosphonomethyl)benzoic acid (2-pmbH3) are reported, namely, Co2(μ4-OH)(2-pmb) (1) and Cu4(μ3-OH)2(2-pmb)2 (2). Both crystallize in polar space groups and show layered structures. Compound 1 contains unusual μ4-OH bridged double chains of {Co2(μ4-OH)O3}, inter-connected by the phosphonate groups. In 2, chair-like tetramers of Cu4(μ3-OH)O2 are linked by both carboxylate and phosphonate groups. Magnetic studies reveal that compound 1 experiences canted antiferromagnetic ordering below 31.0 K with a large coercivity of 4.3 Tesla at 2 K.

Mohamed Abarbri - One of the best experts on this subject based on the ideXlab platform.

Emilie Thiery - One of the best experts on this subject based on the ideXlab platform.

Daniel R. Talham - One of the best experts on this subject based on the ideXlab platform.

  • Structural Characterization and Magnetic Order in Phenoxy-Substituted Divalent Metal Phosphonate Langmuir–Blodgett Films
    IEEE Journal of Solid-state Circuits, 1999
    Co-Authors: Gail E Fanucci, Melissa A Petruska, Mark W. Meisel, Daniel R. Talham
    Abstract:

    Abstract Metal phosphonate Langmuir–Blodgett (LB) films of an alkoxyphenyl-substituted phosphonic acid (P4A) have been prepared with the divalent metals Mn 2+ and Cd 2+ . Structural characterization with infrared spectroscopy, XPS, and X-ray diffraction shows that the films contain the inorganic continuous lattice of known layered solid-state metal phosphonates with formula M (O 3 P R )H 2 O. Magnetic characterization of the Mn-P4 LB film consists of EPR and magnetometry measurements. The Mn-P4 LB film undergoes a transition to a long-range, canted antiferromagnetic state below 14.8±0.2 K and is only the second example of a continuous lattice LB film to exhibit spontaneous magnetization. These results demonstrate that it is possible to prepare metal phosphonate LB films of functionalized organophosphonic acids while retaining both the inorganic continuous lattice structure and magnetic exchange pathways of the known solid-state metal organophosphonates.

  • Langmuir−Blodgett Films of Known Layered Solids: Preparation and Structural Properties of Octadecylphosphonate Bilayers with Divalent Metals and Characterization of a Magnetic Langmuir−Blodgett Film
    Journal of the American Chemical Society, 1997
    Co-Authors: Candace T. Seip, Garrett E. Granroth, Mark W. Meisel, Daniel R. Talham
    Abstract:

    Langmuir−Blodgett (LB) films of a series of divalent metal octadecylphosphonates have been prepared and characterized. The films are each shown to be LB analogs of known solid-state metal phosphonates possessing 2-dimensional ionic−covalent metal phosphonate layers. The metal phosphonate layers crystallize during the LB deposition process. Films were characterized with XPS, X-ray diffraction, ellipsometry, attenuated total reflectance FTIR, and, in the case of the manganese film, SQUID magnetometry. Octadecylphosphonate films with Mn2+, Mg2+, and Cd2+ form with the stoichiometry M(O3PC17H37)·H2O and have metal phosphonate bonding consistent with the analogous M(O3PR)·H2O layered solids. The Ca2+ film forms as Ca(HO3PC18H37)2, which is also a known solid-state phase. Magnetic measurements reveal that the manganese octadecylphosphonate film undergoes a magnetic ordering transition at 13.5 K resulting in a “weak ferromagnet”. The behavior is similar to that of the known layered solid-state manganese alkylpho...

  • Organic/Inorganic Langmuir-Blodgeti Films Based on Metal Phosphonates
    MRS Proceedings, 1997
    Co-Authors: Daniel R. Talham, Melissa A Petruska, Gail E Fanucci, Candace T. Seip
    Abstract:

    AbstractLangmuir-Blodgett (LB) bilayers of organophosphonic acids can be prepared where the phosphonic acid headgroups bind metal ions to form the same layered extended-solid structures present in solid-state metal phosphonates. The inorganic extended-solid network enhances the stability of the LB films, but can also be designed to introduce physical properties, such as magnetism, that are typical of the inorganic solid-state. By preparing films based on functionalized organophosphonic acids, the metal phosphonate approach can be used to produce “dualnetwork” LB films, where both the organic and inorganic networks add function to the thin film assembly. To begin to understand the design constraints associated with dual-network metal phosphonate films, LB bilayers of a phosphonic acidderivatized azobenzene amphiphile are formed with Cd2+ and La3+ and the structures are compared to octadecylphosphonate LB films prepared with the same metals.

Abraham Clearfield - One of the best experts on this subject based on the ideXlab platform.

  • Chapter 1:The Early History and Growth of Metal Phosphonate Chemistry
    Metal Phosphonate Chemistry, 2011
    Co-Authors: Abraham Clearfield
    Abstract:

    This chapter begins with the report by Alberti and co-workers on the synthesis of zirconium phosphonates. It then provides details on the subsequent development of this class of compounds. The reader is then presented with early studies on divalent and trivalent phosphonates, with aluminum phosphonates being treated separately. After a listing of review articles covering the period up to the year 2000, topics of primary interest to the author's research are treated. These include staged materials, functionalization of metal phosphonates and porous pillared nanostructures of four-valent and aluminum phosphonates. Applications in catalysis, ion exchange, proton conduction and nuclear separations are described. A final section describes some interesting results concerned with monovalent phosphonates. The 18 chapters that make up the rest of the book are a testament to the enormous growth and variety of studies in metal phosphonate chemistry.

  • hydrothermal syntheses characterizations and crystal structures of three new cadmium ii amino diphosphonates effects of substitute groups on the structures of metal phosphonates
    Journal of Solid State Chemistry, 2003
    Co-Authors: Bingping Yang, Abraham Clearfield
    Abstract:

    Abstract Hydrothermal reactions of cadmium(II) chloride with three amino-diphosphonic acids, C6H5CH2N(CH2PO3H2)2 (H4L1), C6H5CH2CH2N(CH2PO3H2)2 (H4L2) and 4-CH3–C6H4CH2N (CH2PO3H2)2) (H4L3) resulted in three new metal amino-diphosphonates, namely, Cd(H3L1)2, 1 Cd(H3L2)2·2H2O 2 and Cd(H3L3)2 3. In all three complexes, the Cd(II) ion is octahedrally coordinated by six phosphonate oxygen atoms from six ligands. Complexes 1 and 3 have a similar structure in which the CdO6 octahedra are cross-linked by bridging ligands into a double chain along the c-axis, such double chains are further interlinked via hydrogen bonds between non-coordinated phosphonate oxygen atoms to form 〈100〉 and 〈200〉 layers with the phenyl groups of the ligands orientated toward the interlayer space. The structure of complex 2 features a 〈100〉 cadmium(II) diphosphonate layer. The effects of the substitute groups attached to the amine groups on the structures of the metal phosphonates are also discussed.

  • Synthesis and crystal structures of two metal phosphonates, M(HO3PC6H5)2(M = Ba, Pb)
    Journal of Materials Chemistry, 1996
    Co-Authors: Damodara M Poojary, Sebastian Brogue, Aurelio Cabeza, Baolong Zhang, Miguel A G Aranda, Abraham Clearfield
    Abstract:

    Divalent metal phosphonates, Ba(HO3PC6H5)2 and Pb(HO3PC6H5)2, have been synthesized and structurally characterized [crystal data: a= 32.18(l), b= 5.546(4), c= 8.495(4)A, β= 103.21(3)°, space group C2/c and Z= 4 for Ba(HO3PC6H5)2; a= 31.8302(10), b= 5.5997(2), c= 8.2935(3)A, β= 101.875(2)°, space group C2/c and Z= 4 for Pb(HO3PC6H5)2]. Their structures are isomorphous. The structure of the barium compound was solved from single-crystal data which was then used to refine the-structure of the lead compound by Rietveld methods. In these compounds the metal: phosphonate ratio is 1 : 2 and the phosphonates use all their oxygens to bridge the metal atoms, which are arranged in two-dimensional layers, One of the phosphonate oxygens is protonated. The phosphonate oxygens are involved in both chelation and bridging interactions. The metal atoms are eight-coordinate; four of the binding sites are due to symmetry-related positions of a single oxygen atom and two each from the remaining two oxygen atoms.

  • synthesis and crystal structures of two metal phosphonates m ho3pc6h5 2 m ba pb
    Journal of Materials Chemistry, 1996
    Co-Authors: Damodara M Poojary, Sebastian Brogue, Aurelio Cabeza, Baolong Zhang, Miguel A G Aranda, Abraham Clearfield
    Abstract:

    Divalent metal phosphonates, Ba(HO3PC6H5)2 and Pb(HO3PC6H5)2, have been synthesized and structurally characterized [crystal data: a= 32.18(l), b= 5.546(4), c= 8.495(4)A, β= 103.21(3)°, space group C2/c and Z= 4 for Ba(HO3PC6H5)2; a= 31.8302(10), b= 5.5997(2), c= 8.2935(3)A, β= 101.875(2)°, space group C2/c and Z= 4 for Pb(HO3PC6H5)2]. Their structures are isomorphous. The structure of the barium compound was solved from single-crystal data which was then used to refine the-structure of the lead compound by Rietveld methods. In these compounds the metal: phosphonate ratio is 1 : 2 and the phosphonates use all their oxygens to bridge the metal atoms, which are arranged in two-dimensional layers, One of the phosphonate oxygens is protonated. The phosphonate oxygens are involved in both chelation and bridging interactions. The metal atoms are eight-coordinate; four of the binding sites are due to symmetry-related positions of a single oxygen atom and two each from the remaining two oxygen atoms.