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1.
J Econ Entomol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579138

RESUMO

Metarhizium anisopliae is an important class of entomopathogenic fungi used for the biocontrol of insects, but its virulence is affected by insect immunity. We identified a novel FK506 binding protein gene that was differentially expressed between control and Metarhizium-treated Locusta migratoria manilensis. We hypothesized that this protein played an important role in Metarhizium infection of L. migratoria and could provide new insights for developing highly efficient entomopathogenic fungi. We, therefore, cloned the specific gene and obtained its purified protein. The gene was then named FKBP52, and its dsRNA (dsFKBP52) was synthesized and used for gene interference. Bioassay results showed that the mortality of L. migratoria treated with dsFKBP52 + Metarhizium was significantly lower than that of other treatments. Furthermore, immune-related genes (MyD88, Dorsal, Cactus, and Defensin) in L. migratoria treated with dsFKBP52 + Metarhizium showed significant upregulation compared to that treated with Metarhizium only. However, the activities of peroxidase (POD), superoxide dismutase (SOD), and calcineurin (CaN) showed fluctuations. These results suggest that the FKBP52 gene may play a crucial role in the innate immunity of L. migratoria. The effect of its silencing indicated that this immunity-related protein might be a potential target for insect biocontrol.

2.
Inorg Chem ; 62(38): 15527-15536, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37696003

RESUMO

Deep-ultraviolet (DUV) nonlinear optical (NLO) materials play a crucial role in cutting-edge laser technology. In order to solve the serious layered growth tendency of the sole commercial DUV NLO crystal KBe2BO3F2 (KBBF), developing alternative systems of compounds with bulk crystal habits has become an urgent task for practical applications. Herein, a novel strategy was developed by applying non-centrosymmetric (NCS) cancrinite (CAN)-type zincophosphates {Na6(OH)2(H2O)2}Cs2[ZnPO4]6 with bulk-crystal habits as the prototype to design new DUV NLO crystals. Two new anhydrous alkali zincophosphates, namely, {(Li6 -xNaxO)A2}[(ZnPO4)6] (A = Cs, Rb; x = 2-3) crystallizing in the NCS hexagonal space group P63 (no. 173) with a CAN-type framework, were successfully synthesized via a modified fluoro-solvo-hydrothermal method by applying triethylamine (TEA) and concentrated NaF solution as a co-solvent. Interestingly, the rigidity of the NCS CAN-type framework acting as the host ensures the non-centrosymmetry of the resulting new compounds. Meanwhile, the replacement of water molecules by guest cationic species in the channels or cages can greatly improve the thermal stability of the resultant crystal and tune its NLO properties. The synergetic effect of the host framework and the guest species makes the two compounds transparent down to the DUV region (<200 nm) and exhibit SHG effects. Therefore, the proposed rational design strategy of applying the known zeotype NCS frameworks as prototypes together with the modified fluoro-solvo-hydrothermal method opens a great avenue for highly effectively exploring new DUV NLO materials.

3.
Inorg Chem ; 62(35): 14431-14438, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37622651

RESUMO

Developing strategies to rational design noncentrosymmetric structure still attract much interest for their applications in nonlinear optical and piezoelectric materials. Two noncentrosymmetric (NCS) alkaline earth metal bismuth phosphates have been successfully achieved via partial replacement of Bi3+ with Ca2+ or Sr2+ ions. BiCa(H0.5PO4)2 (designated as CaBiPO) and BiSr(H0.5PO4)2 (designated as SrBiPO), together with their solid solution Bi(Sr1-xCax)(H0.5PO4)2 (0 < x ≤ 0.5), crystallize in the NCS space group C2. Both CaBiPO and SrBiPO exhibit ultraviolet nonlinear optical (NLO) properties, and their second-harmonic generation effects belong to type-II phase matching. Meanwhile, they could also act as photoluminescence hosts in which the Eu3+-doping samples SrBiPO:xEu3+ (x = 0.02-0.2) emit orange light. The effect of different radius ions on the derivative structures and the structure-NLO property relationship has also been discussed in detail.

4.
Natl Sci Rev ; 10(3): nwac237, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37063704

RESUMO

Aromatic metallacycles are of considerable current interest. Reported aromatic metallacycles are mainly those with carbon, nitrogen, oxygen and sulfur. In this work, we report the synthesis and characterization of aromatic chloroosmacyclopentatrienes, which represent the first structurally confirmed metallaaromatic with a chlorine atom in its framework. Single-crystal X-ray diffraction studies show that these planar chloroosmacyclopentatrienes possess a very short Os-ClC distance suggesting M=ClC bond character.

5.
Waste Manag ; 163: 144-153, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37015150

RESUMO

Excavation waste from the construction of subways and other underground infrastructures is mainly composed of gravel, sand and clay of minimal economic value, which commonly ends up in landfills. Although the coarse sand and gravel of the excavation waste are typically recycled on site, a large amount of the fine-grained residue must be disposed of due to the prohibition of marine land reclamation in Xiamen, China, leading to an increasingly severe shortage of landfills. In this contribution, a new strategy was successfully developed for industrial-scale extraction of high value-added kaolin from the excavation waste of Xiamen. This strategy can overcome the challenges of complex and variable chemical compositions, high iron contents, low industrial grade, and organic contaminants in the raw materials. Characterization using chemical analysis, powder X-ray diffraction, scanning electron microscopy, and infrared spectroscopy showed that the Xiamen excavation waste originated from granite weathering is mainly composed of kaolinite and quartz, along with high Fe contents and other impurities. The excavation waste was subjected to an intensive process of blunging, grinding, sieving, and classifying, as well as successive iron removal by magnetic separation. Subsequently, the extracted products meet commercial requirements, including those for high-quality kaolin with whiteness and plasticity larger than 90° and 17%, respectively. Moreover, an industrial-scale green production line with an annual treatment capacity of one million tonnes of excavation waste at the utilization rate of 100% was implemented. Hence, this work presents an effective approach for exploiting similar excavation waste around the world to promote sustainable development.


Assuntos
Caulim , Areia , Caulim/química , Argila , Instalações de Eliminação de Resíduos , Ferro , Resíduos Industriais
6.
Dalton Trans ; 50(22): 7835-7842, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34008671

RESUMO

Magnetism of any material depends on its crystal structure. However, two isostructural compounds such as MCuMoO4(OH) (M = Na, K) can have markedly different magnetic properties. Herein, we introduce a new method to describe the linkages between the O-atoms and their bridged Cu2+ ions in order to clearly illustrate the structure-magnetic property relationships. This new method can account for magnetic differences between the two isostructural MCuMoO4(OH) and is further confirmed by the rational design and development of a new compound KGaCu(PO4)2 with different linkages. The title compound crystalized in a space group of P21/c adopts a one-dimensional (1D) magnetically isolated S = 1/2 zigzag chain composed of elongated [CuO6] octahedra via sharing alternately equatorial and skew edges. O atoms at the skew edges bridge the equatorial and axial orbitals of neighbouring Cu2+ ions (denoted EOA), while those at the equatorial edges bridge the equatorial orbitals of Cu2+ ions (EOE). The nearest-neighbour (NN) magnetic coupling of Cu2+ ions with the EOA linkage at 2.821 Å in the title compound is negligible, whereas the NN magnetic coupling of Cu2+ ions with the EOE linkage at 2.974 Å is essential. Therefore, the zigzag chain containing alternating spin-exchange dimers and no-spin-exchange ones is similar in electronic configuration to the dimerization of the quasi-one-dimensional antiferromagnet. Magnetic investigation of analogous compounds with a 'trans-cis-trans-cis' configuration observed in the title compound may shed light on structural evolutions associated with spin-Peierls (SP) transition.

7.
Inorg Chem ; 58(7): 4508-4514, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30864428

RESUMO

Rational design and tailored synthesis of noncentrosymmetric compounds with nonlinear optical (NLO) properties, especially in the deep-ultraviolet (deep-UV) region, remains a great challenge. Herein, we report on the development of a modified fluoro-solvo-hydrothermal method with two additive reagents (trimethylamine and NaF solution) as the solvents, using BaFe(PO4)(OH) ( P212121) as the prototype, for the rational design and tailored synthesis of the first deep-UV fluorinated orthophosphate, BaZn(PO4)F. It crystallizes in the polar space group Pna21 and exhibits transparency down to deep-UV region (<190 nm) with SHG effect at 0.26 × KH2(PO4). Its structure is built from strictly alternating ZnO4F trigonal bipyramids and PO4 tetrahedra, resulting in a four-connected ABW-type zeolite framework. First-principles calculations confirm the deep-UV absorption edge and reveal that ZnO4F plays an essential role in the NLO properties. The synergetic effect of Zn and F atoms leads to its more polar crystal structure, much deeper absorption edge, and better SHG effect than the prototype.

8.
Dalton Trans ; 46(35): 11851-11859, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28848945

RESUMO

Germanophosphates, in comparison with other metal phosphates, have been less studied but potentially exhibit more diverse structural chemistry with wide applications. Herein we applied a hydro-/solvo-fluorothermal route to make use of both the "tailor effect" of fluoride for the formation of low dimensional anionic clusters and the presence of alkali cations of different sizes to align the anionic clusters to control the overall crystal symmetries of germanophosphates. The synergetic effects of fluoride and alkali cations led to structural changes from chain-like structures to layered structures in a series of five novel fluorogermanophosphates: A2[GeF2(HPO4)2] (A = Na, K, Rb, NH4, and Cs, denoted as Na, K, Rb, NH4, and Cs). Although these fluorogermanophosphates have stoichiometrically equivalent formulas, they feature different anionic clusters, diverse structural dimensionalities, and contrasting crystal symmetries. Chain-like structures were observed for the compounds with the smaller sized alkali ions (Na+, K+, and Rb+), whereas layered structures were found for those containing the larger sized cations ((NH4)+ and Cs+). Specifically, monoclinic space groups were observed for the Na, K, Rb, and NH4 compounds, whereas a tetragonal space group P4/mbm was found for the Cs compound. These compounds provide new insights into the effects of cation sizes on the anionic clusters built from GeO4F2 octahedra and HPO4 tetrahedra as well as their influences on the overall structural symmetries in germanophosphates. Further characterization including IR spectroscopy and thermal analyses for all five compounds is also presented.

9.
Dalton Trans ; 46(29): 9535-9541, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28702632

RESUMO

Herbertsmithite- and kapellasite-type compounds with triangular lattices (i.e. Kagomé) as the most promising candidates for realizing the exotic quantum spin liquid (QSL) state have recently attracted significant attention in condensed matter physics and materials science but are often adversely affected by dimensional imperfections arising from significant cation mixing. Also, interaction mechanisms between the Kagomé lattices and ionic impurities remain unclear. Herein we report on the synthesis, crystal structures and magnetic properties of a new class of kapellasite-type compounds LnCu3(OH)6Cl3 (Ln = Nd and Sm) with two overlapped triangular lattices. These compounds are characterized by the triangular lattices of Cu2+ superimposed by another triangular lattice of paramagnetic Ln3+. The magnetic properties of LnCu3(OH)6Cl3 feature strong spin frustrations as well as antisymmetrical Dzyaloshinskii-Moriya interactions resulting in canted antiferromagnetic ordering with the Néel temperature (TN) of ∼20 K and ∼18 K for NdCu3(OH)6Cl3 and SmCu3(OH)6Cl3, respectively. Moreover, negative magnetization at low temperatures was firstly observed in Kagomé lattice compounds, arising from geometrical spin frustration and competing interactions within two overlapped triangular lattices.

10.
Dalton Trans ; 46(5): 1677-1683, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28098285

RESUMO

Two challenges to grow KBe2BO3F2 (KBBF), the best known deep-ultraviolet nonlinear optical (NLO) material to date, are the limited crystal sizes and the use of a highly toxic element (Be). Herein we report on the discovery of a novel anhydrous non-centrosymmetric alkali fluorinated borophosphate KB(PO4)F (KBPF) featuring a cut-off wavelength of less than 200 nm and a large second-harmonic generation (SHG) effect similar to KH2PO4 (KDP), hence representing a new promising deep-ultraviolet NLO material. The KBPF crystals consisting of common elements can be grown using green and cost effective processes and do not show any detectable hygroscopicity. The title compound also features a 2-dimensional layer [BPO4F]∞ built from [BO3F]4- and [PO4]3- tetrahedral groups but has much stronger interlayer bonds than KBBF, allowing the growth of large crystals. The title compound has been characterized by PXRD, SEM, TG-DSC, FTIR, UV-Vis-NIR diffuse reflectance and SHG analyses as well as single-crystal X-ray structure refinements. The optical properties of KBPF have also been evaluated by first-principles calculations at the density functional theory (DFT) level.

11.
Inorg Chem ; 55(23): 12376-12382, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27934425

RESUMO

Anhydrous compounds are crucially important for many technological applications, such as achieving high performance in lithium/sodium cells, but are often challenging to synthesize under hydrothermal conditions. Herein we report that a modified solvo-/hydro-fluorothermal method with fluoride-rich and water-deficient condition is highly effective for synthesizing anhydrous compounds by the replacement of hydroxyl groups and water molecules with fluorine. Two anhydrous phosphate germanium fluorides, namely, Na3[GeF4(PO4)] and K4[Ge2F9(PO4)], with chainlike structures involving multiple fluorine substitutions, were synthesized using the modified solvo-/hydro-fluorothermal method. The crystal structure of Na3[GeF4(PO4)] is constructed by the common single chains ∞1{[GeF4(PO4)]3-} built from alternating GeO2F4 octahedra and PO4 tetrahedra. For K4[Ge2F9(PO4)], it takes the same single chain in Na3[GeF4(PO4)] as the backbone but has additional flanking GeOF5 octahedra via an O-corner of the PO4 groups, resulting in a dendrite zigzag single chain ∞1{[Ge2F9(PO4)]4-}. The multiple fluorine substitutions in these compounds not only force them to adopt the low-dimensional structures because of the "tailor effect" but also improve their thermal stabilities. The thermal behavior of Na3[GeF4(PO4)] was investigated by an in situ powder X-ray diffraction experiment from room temperature to 700 °C. The modified solvo-/hydro-fluorothermal method is also shown to be effective in producing the most germanium-rich compounds in the germanophosphate system.

12.
Sheng Wu Gong Cheng Xue Bao ; 32(5): 635-647, 2016 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-29019201

RESUMO

The heterochronic genes regulate cell proliferation and switch development stage transitions. Heterochronic genes might also play important roles in regulating the development of silkworm, but very few of their expression profiles, functions and their relationship with microRNAs are available so far. Firstly, in this work, the primers for cloning Bmlin-41 were designed based on the homologous sequence of known Drosophila melanogaster lin-41, which was used as the query to blast against SilkDB. The obtained full CDS (2 166 bp) of Bmlin-41 encodes 721 amino acids and contains B-box and NHL domains. Then, the spatiotemporal expression patterns of Bmlin-41 were characterized by RT-PCR, quantitative real time PCR as well as our lab's previous silkworm genome microarray data. Bmlin-41 was increasingly expressed from embryonic to adult stage. In diverse tissues of day-3 fifth instar, Bmlin-41 showed the highest accumulation in ovary, secondly in testis and midgut, but very low expression was observed in other tissues. Finally, 3'UTR of Bmlin-41 1 434 bp was cloned by rapid-amplification of cDNA ends (3'RACE) and was predicted to bare two binding sites of bmo-let-7 by using online RNAhybrid. To verify the binding effect, 3'UTR was cloned into psi-CHECK-2 vector and submitted to dual luciferase assay in the S2 cells in vitro. The dual luciferase assay demonstrated that Bmlin-41 was down-regulated by bmo-let-7 mimics and upregulated by bmo-let-7 antagomir, thus confirming the Bmlin-41 is negatively regulated by bmo-let-7. Our work might help further study on the roles of Bmlin-41 and bmo-let-7 and their regulation relationship involved in controlling metamorphosis of silkworm.


Assuntos
Bombyx , Proteínas de Insetos/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo , Regiões 3' não Traduzidas , Animais , Clonagem Molecular , DNA Complementar , Regulação para Baixo , Drosophila melanogaster , Regulação da Expressão Gênica , Proteínas de Insetos/genética , Metamorfose Biológica , Fatores de Transcrição/genética
13.
Inorg Chem ; 54(14): 6978-85, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26114372

RESUMO

The "tailor effect" of fluoride, exclusively as a terminal rather than a bridge, was applied successfully to design low-dimensional structures in the system of transition metal germanophosphates for the first time. Two series of new compounds with low-dimensional structures are reported herein. K[M(II)Ge(OH)2(H0.5PO4)2] (M = Fe, Co) possess flat layered structures built from single chains of edge-sharing M(II)O6 and GeO6 octahedra interconnected by HPO4 tetrahedra. Their fluorinated derivatives, K4[M(II)Ge2F2(OH)2(PO4)2(HPO4)2]·2H2O (M = Fe, Co), exhibit band structures of two four-membered ring germanium phosphate single chains sandwiched by M(II)O6 octahedra via corner-sharing. Both of these structures contain anionic chains of the condensation of four-membered rings built from alternating GeO4Φ2 (Φ = F, OH) octahedra and PO4 tetrahedra via sharing common GeO4Φ2 (Φ = F, OH) octahedra, the topology of which is the same as that of the mineral kröhnkite [Na2Cu(SO4)2·2H2O]. Note that the switch from the two-dimensional layered structure to the one-dimensional band structure was performed simply by the addition of a small amount of KF·2H2O to the reaction mixture. This structural alteration arises from the incorporation of one terminal F atom to the coordination sphere of Ge, which breaks the linkage between the transition metal and germanium octahedra in the layer to form the band structure.

14.
Acta Crystallogr C Struct Chem ; 71(Pt 6): 440-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26044323

RESUMO

The ADDSYM routine in the program PLATON [Spek (2015). Acta Cryst. C71, 9-18] has helped researchers to avoid structures of (metal-)organic compounds being reported in an unnecessarily low symmetry space group. However, determination of the correct space group may get more complicated in cases of pseudosymmetric inorganic compounds. One example is NaVO2F2, which was reported [Crosnier-Lopez et al. (1994). Eur. J. Solid State Inorg. Chem. 31, 957-965] in the acentric space group P21 based on properties but flagged by ADDSYM as (pseudo)centrosymmetric P21/m within default distance tolerances. Herein a systematic investigation reveals that NaVO2F2 exists in at least four polymorphs: P21, (I), P21/m, (II), P21/c, (III), and one or more low-temperature ones. The new centrosymmetric modification, (III), with the space group P21/c has a similar atomic packing geometry to phase (I), except for having a doubled c axis. The double-cell of phase (III) arises from atomic shifts from the glide plane c at (x, », z). With increasing temperature, the number of observed reflections decreases. The odd l reflections gradually become weaker and, correspondingly, all atoms shift towards the glide plane, resulting in a gradual second-order transformation of (III) into high-temperature phase (II) (P21/m) at below 493 K. At least one first-order enantiotropic phase transition was observed below 139 K from both the single-crystal X-ray diffraction and the differential scanning calorimetry analyses. Periodic first-principles calculations within density functional theory show that both P21/c superstructure (III) and P21 substructure (I) are more stable than P21/m structure (II), and that P21/c superstructure (III) is more stable that P21 substructure (I).

15.
Dalton Trans ; 44(17): 7960-6, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25826670

RESUMO

A novel, mixed- and high-valence manganese (Mn(3+)/Mn(4+)) fluorophosphate, Mn(III)6F12(PO3(OH))8[Na8(Kx(H3O)4-x(H2O)2)Mn(IV)(OH)6] (denoted as MN), has been prepared via a water-deficient hydrothermal route with phosphoric acid as the sole solvent. This compound features a cubic three-dimensional open-framework structure built from corner-sharing [Mn(III)O4F2] octahedra and [HPO4] groups, which encapsulates a clathrate-like "guest cluster" of Na8(Kx(H3O)4-x(H2O)2)Mn(IV)(OH)6. The guest cluster is architecturally composed of a [Mn(IV)(OH)6] octahedron in a cubic cage of Na(+) cations, which in turn is surrounded by an octahedral arrangement of K(+)/H2O ions, resulting in an unprecedented octahedral @ cubic @ octahedral @ cubic arrangement (OCOC). The +4 oxidation state of Mn in the guest cluster has been confirmed by the synthesis of isotypic Ti- and Ge- analogues (denoted as TI and GE) using TiO2 and GeO2 as the replacement for MnO2 in the starting materials. The compounds MN, TI and GE are not stable in aqueous solution and are peeled off layer-by-layer after the absorption of water. This report provides a new route for the synthesis of mixed- and high-valence manganese phosphates that cannot be produced by conventional hydrothermal methods.

16.
Sheng Wu Gong Cheng Xue Bao ; 31(11): 1612-22, 2015 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-26939444

RESUMO

microRNAs (miRNAs) are an extensive class of -22-nucleotide (nt) endogenous noncoding RNAs regulating life activities ofmetazoans through binding to 3'-untranslated regions (3'-UTRs) of their target genes. This work aimed to identify yan gene in the silkworm, reveal its expression profile and confirm if it is one target of bmo-miR-7 and, as such, have potential for contributing to better understanding of the molecular mechanisms involved in the metamorphosis of silkworm. Based on homolog searching and PCR amplification, we cloned the coding sequence (CDS) of Bmyan, which encodes 476 amino acid residues and contains SAM-PNT and ETs domains. Quantitative PCR (q-PCR), RT-PCR and microarray data revealed high expression of Bmyan in the head, body wall and ovary of day-3 fifth instar larval silkworm, low or no expression in other tissues. It was lowly expressed in the early larval stages, but highly expressed from late spinning to day 4 pupa. The 3'-UTR of Bmyan was obtained by rapid-amplification of cDNA ends (3'RACE) and predicted to contain two potential recognition sites of bmo-miR-7. The luciferase reporter vector containing the 3'-UTR of Bmyan was constructed and co-transfected into BmE cell line with the mimic of bmo-miR-7 and the decreased relative activity of luciferase showed that Bmyan is one target of bmo-miR-7. This work helps further functional analysis of bmo-miR-7 and Bmyan in the silkworm.


Assuntos
Bombyx/genética , Proteínas de Insetos/genética , MicroRNAs/genética , Regiões 3' não Traduzidas , Animais , Linhagem Celular , Clonagem Molecular , Feminino , Vetores Genéticos , Larva , Metamorfose Biológica , Pupa
17.
Inorg Chem ; 52(16): 9169-71, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-23927559

RESUMO

Structural assembly from phosphate to germanophosphate by applying germanate as a binder has been achieved. Two isotypic porous compounds, K3[M(II)4(HPO4)2][Ge2O(OH)(PO4)4]·xH2O (M(II) = Fe, Cd; x = 2 for Fe and 3 for Cd, denoted as KFeGePO-1 and KCdGePO-1, respectively), contain a known transition-metal phosphate (TMPO) layer, (∞)(2){[M2(HPO4)3]2­}, which is built from chains of trans-edge-sharing MO6 octahedra bridged by MO5 trigonal bipyramids that were further linked and decorated by phosphate tetrahedra. The layers are bound by infinite chains of GeO5(OH) octahedra, resulting in a 3D open-framework structure with 1D 12-ring channels that are occupied by K+ ions and water molecules. The curvature of the TMPO layers and shape of the 12-ring windows can be tuned by the transition metals because of their Jahn­Teller effect.


Assuntos
Germânio/química , Metais/química , Fosfatos/química , Modelos Moleculares , Estrutura Molecular
18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): i47-i48, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719277

RESUMO

The title compound, dipotassium diaqua-bis-(diphosphato)triferrate(II), K(2)[Fe(II) (3)(P(2)O(7))(2)(H(2)O)(2)], was synthesized under solvothermal conditions. The crystal structure is isotypic with its Co analogue. In the structure, there are two crystallographically distinct Fe positions; one lies on an inversion center, the other on a general position. The first Fe(2+) cation adopts a regular octa-hedral coordination with six O atoms, whereas the other is coordinated by five O atoms and a water mol-ecule. The [FeO(6)] octa-hedron shares its trans-edges with an adjacent [FeO(5)(H(2)O)] octahedron; in turn, the [FeO(5)(H(2)O)] octa-hedron shares skew-edges with a neighbouring [FeO(6)] octa-hedron and an [FeO(5)(H(2)O)] octa-hedron, resulting in a zigzag octa-hedral chain running along [001]. The zigzag chains are linked to each other by the P(2)O(7) diphosphate groups, leading to a corrugated iron diphosphate layer, [Fe(3)(P(2)O(7))(2)(H(2)O)(2)](2-), parallel to (100). The inter-layer space is occupied by K(+) cations, which adopt an eight-coordination to seven O atoms and one water mol-ecule from a neighbouring iron diphosphate layer. Thus, the K(+) ions not only compensate the negative charge of the layer but also link the layers into a network structure.

19.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): i33-i34, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590053

RESUMO

The crystal structure of Ce[B(5)O(8)(OH)(H(2)O)]NO(3)·2H(2)O, cerium(III) aqua-hydroxidoocta-oxidopenta-borate nitrate dihydrate, has been redetermined from single-crystal X-ray diffraction data. In contrast to the previous determination [Li et al. (2003 ▶). Chem. Mater.15, 2253-2260], the present study reveals the location of all H atoms, slightly different fundamental building blocks (FBBs) of the polyborate anions, more reasonable displacement ellipsoids for all non-H atoms, as well as a model without disorder of the nitrate anion. The crystal structure is built from corrugated polyborate layers parallel to (010). These layers, consisting of [B(5)O(8)(OH)(H(2)O)](2-) anions as FBBs, stack along [010] and are linked by Ce(3+) ions, which exhibit a distorted CeO(10) coordination sphere. The layers are additionally stabilized via O-H⋯O hydrogen bonds between water mol-ecules and nitrate anions, located at the inter-layer space. The [BO(3)(H(2)O)]-group shows a [3 + 1] coordination and is considerably distorted from a tetra-hedral configuration. Bond-valence-sum calculation shows that the valence sum of boron is only 2.63 valence units (v.u.) when the contribution of the water mol-ecule (0.49 v.u.) is neglected.

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): i37-i38, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590056

RESUMO

The title compound, Mn(4)(H(2)O)(4)[Ge(OH)(2)(HPO(4))(2)(PO(4))(2)], was synthesized by the solvothermal method. Its crystal structure is isotypic with the iron and cobalt analogues [Huang et al. (2012 ▶). Inorg. Chem.51, 3316-3323]. In the crystal structure, the framework is built from undulating manganese phosphate sheets parallel to (010) inter-connected by GeO(6) octa-hedra (at the inversion center), resulting in a three-dimensional network with eight-membered ring channels into which all the protons point. The undulating manganese phosphate sheet consists of zigzag manganese octa-hedral chains along [10-1], built from MnO(4)(OH)(OH(2)) octa-hedra and MnO(5)(OH(2)) octa-hedra by sharing their trans or skew edges, which are inter-connected by PO(3)(OH) and PO(4) tetra-hedra via corner-sharing. The crystal structure features extensive O-H⋯O hydrogen-bonding inter-actions.

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