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An exploratory study of the lead-tellurium-oxygen phase space led to two new compounds, Ba3PbTe6O16 (BPTO) and Na2Pb9(μ6-O)2(Te2O10)2 (NPTO), which were synthesized under hydrothermal conditions at 550 °C and 210 °C, respectively, and characterized by single-crystal X-ray diffraction, infrared and X-ray photoelectron spectroscopy. BPTO adopts a layer structure. The Te4+ cation in BPTO is bonded to four oxygen atoms at about 2.0 A with two more oxygens at about 3.0 A. The seesaw-shaped TeO4 units share corners to form 2D layers containing six-membered rings and the Ba2+ and Pb2+ cations are situated in the interlayer region. The structure of NPTO contains dimers of edge-sharing Te6+O6 octahedra, which are connected through five-coordinate Pb2+ cations. A unique six-coordinate O atom is at the center of the octahedron formed by five Pb2+ and one Na+ cations. BPTO is one of the few metal tellurites which were synthesized under supercritical hydrothermal reaction conditions. The Pb2+ cation in NPTO shows pronounced stereochemical effects of the lone electron pair. In contrast, BPTO shows no stereochemical evidence of the inert pair.

A new lead(ii) borosilicate, Pb6B2Si8O25 (1), has been synthesized by a high-temperature, high-pressure hydrothermal reaction at 480 °C and 990 bar. Its structure was determined by single-crystal X-ray diffraction. The reaction product was phase-pure as indicated by powder X-ray diffraction and whole pattern fitting using the Pawley method. Compound 1 has a 2D layer structure with the lead ions being located at interlayer regions. Each layer is formed of corner-sharing BO4 or SiO4 tetrahedra and contains an eight-ring window. The layer consists of a new fundamental building block (FBB) with the formula T8O23 (T: B or Si) formed by two (B(1)0.8Si(1)0.2)O4 tetrahedra and six (Si(2)0.933B(2)0.067)O4 tetrahedra. The FBB can be described as double open-branched triple tetrahedra. Another interesting structural feature of 1 is boron-silicon mixing which is uncommon in borosilicates. There are three unique tetrahedra in the structure: B(1)O4 tetrahedra with 20% substitution of Si for B, Si(2)O4 tetrahedra with 6.67% substitution of B for Si, and Si(3)O4 tetrahedra without substitution. We have applied 11B and 29Si MAS NMR spectroscopy to study the substitutional disorder. The NMR study results not only confirm the mixing of B and Si atoms in the structure, but also verify quantitatively the results from single-crystal X-ray diffraction. The reasons for boron-silicon mixing in the structure are discussed. Crystal data for 1: trigonal, R3[combining macron]c (no. 167), a = 9.5090(2) A, c = 42.3552(8) A, V = 3316.7(2) A3, Z = 6, R1 = 0.0147, and wR2 = 0.0309.

With a high-temperature, high-pressure hydrothermal technique, a new barium lead borate, [Ba3Pb(H2O)][B11O19(OH)3] (1), has been synthesized and characterized by single-crystal X-ray diffraction, and infrared and solid-state NMR spectroscopy. The structure of 1 contains planar thick layers of borates with the Ba2+ cations at sites in the inter- and intralayer space. Each layer consists of three single sheets. The central sheet is very corrugated and is built up from the fundamental building block (FBB) 2Δ3□:〈Δ2□〉–〈Δ2□〉. On both sides of the central sheet there are borate single chains formed of the very rare FBB 2Δ4□:〈Δ2□〉–〈3□〉Δ via corner-sharing. This FBB was first observed in a high-pressure polymorph of CaB2O4. These chains are linked into a sheet by PbO5(H2O) polyhedra, which are further linked to the central sheet by sharing vertices between triangles and tetrahedra to form a thick layer. The IR spectrum shows the presence of hydroxyl groups of HBO4, water molecules, BO3 triangles, and BO4 tetrahedra. The presence of BO3 and BO4 polyhedra was also confirmed by 11B MAS NMR spectroscopy.

Two polymorphs of a new barium borate, α- and β-Ba3[B10O17(OH)2], have been synthesized through hydrothermal reactions at 500 °C and 1000 bar and their structures determined by single-crystal X-ray...

A tullurate containing a new type of finite oligomer with Te6+ only was synthesized by a high-temperature, high-pressure hydrothermal method.

With a high-temperature, high-pressure hydrothermal technique, a new barium lead borate, [Ba3Pb(H2O)][B11O19(OH)3] (1), has been synthesized and characterized by single-crystal X-ray diffraction, and infrared and solid-state NMR spectroscopy. The structure of 1 contains planar thick layers of borates with the Ba2+ cations at sites in the inter- and intralayer space. Each layer consists of three single sheets. The central sheet is very corrugated and is built up from the fundamental building block (FBB) 2Δ3□:Δ2□-Δ2□. On both sides of the central sheet there are borate single chains formed of the very rare FBB 2Δ4□:Δ2□-3□Δ via corner-sharing. This FBB was first observed in a high-pressure polymorph of CaB2O4. These chains are linked into a sheet by PbO5(H2O) polyhedra, which are further linked to the central sheet by sharing vertices between triangles and tetrahedra to form a thick layer. The IR spectrum shows the presence of hydroxyl groups of HBO4, water molecules, BO3 triangles, and BO4 tetrahedra. The presence of BO3 and BO4 polyhedra was also confirmed by 11B MAS NMR spectroscopy.

Two new barium borate carbonates, Ba3[B6O10(OH)2](CO3) (1) and Ba6[B12O21(OH)2](CO3)2 (2), have been synthesized by high-temperature, high-pressure hydrothermal methods at 460 °C and 600 bar and structurally characterized by single-crystal X-ray diffraction, TGA, IR, and MAS 11B NMR spectroscopy. The descriptors of the fundamental building blocks (FBB) of both structures are 2Δ4□:⟨Δ2□⟩=⟨4□⟩=⟨Δ2□⟩. The FBB of 1 has a chair conformation, and the FBBs of 2 have both chair and boat conformations. Compound 1 adopts a noncentrosymmetric 2D layer structure with the Ba2+ cations and CO32– anions between the layers, whereas compound 2 has a centrosymmetric 3D framework structure containing 9- and 10-ring channels with the Ba2+ cations and CO32– anions at the center or on the edges of the channels. The two structures are two of the few examples where the carbonate groups are isolated and occupy their own independent sites.

A new borate fluoride, Ba2B5O9F·0.5H2O, has been synthesized by high-temperature, high-pressure hydrothermal method, characterized by a combination of techniques and its structure determined by single-crystal X-ray diffraction. The compound crystallizes in the noncentrosymmetric space group P4n2 (No. 118) and powder SHG measurements were performed to confirm the absence of a center of symmetry. Its crystal structure is formed of a new fundamental building block which shares oxygen atoms with neighboring blocks to form a 3D borate framework with 12- and 8-ring channels where the Ba2+ cations, F– anions, and water molecules are located. The structure is compared with those of minerals and synthetic borate fluoride and chlorides with similar framework compositions. The 11B MAS NMR experimental results are in accord with those from crystal structure analysis and the resonances in the spectrum are assigned. The presence of water was confirmed by IR spectroscopy, and its content and the thermal decomposition p...

A new aluminum borate, Ba[AlB4O8(OH)], has been synthesized under high-temperature, high-pressure hydrothermal conditions at 550 °C and 1400 bar and its structure characterized by single-crystal X-ray diffraction, IR, and MAS 11B, and 27Al NMR spectroscopy. It crystallizes in the monoclinic space group P21/n with a = 7.0695(5) A, b = 15.108(1) A, c = 7.0746(5) A, β = 93.593(2)°, and Z = 4. Its 2D layer structure is formed of corner-sharing B4O8(OH) clusters and AlO4 tetrahedra with the charge-compensating Ba2+ cations between the layers. While the same in the framework composition, the title compound and the hydrate, Ba[AlB4O8(OH)]·H2O, differ greatly in structure. Although the title compound contains an OH group, it is thermally stable up to 740 °C and then decomposes into Ba2Al2B8O17, as indicated by high-temperature DSC/TG analysis and powder X-ray diffraction.

Two new polymorphs of a zinc phosphate incorporating the terephthalate organic ligand 1,4-benzenedicarboxylate (BDC), (H2DA)Zn2(cis-BDC)(HPO4)2 (1) and (H2DA)Zn2(trans-BDC)(HPO4)2 (2), where DA = 1,7-diaminoheptane, were synthesized via a hydro(solvo)thermal method at different reaction temperatures and structurally characterized by single-crystal X-ray diffraction. Interestingly, the BDC ligands, which adopt the bis-monodentate coordination model with a unusual cis type for compound 1 and with a trans linkage for compound 2, bridge the Zn atoms of the inorganic layers in the generation of two polymorphs with structural diversities (one kind of arrangement of the layered zincophosphate layer in 1; the flat and zigzag sheets of inorganic networks in 2). A simple method for tuning the optical luminescence of the title compound from blue, red, green, yellow, and pink to white emission by stirring powdered samples in lanthanide-cation-containing aqueous ethanol solutions at room temperature for 1–2 h is also ...

Correction for 'Ca

A new tellurium(vi) oxycompound, Ca10Na10[Te9O42](H2O), was synthesized by a high-temperature, high-pressure hydrothermal reaction at 550 °C, its structure determined by single-crystal X-ray diffraction, and further characterized by energy dispersive, infrared, and X-ray photoelectron spectroscopy. The compound crystallizes in the centrosymmetric trigonal space group R3[combining macron]c (no. 167) with a = 9.743(2), c = 66.337(13) Å, and Z = 6. The structure consists of discrete linear edge-sharing octahedral trimers with the composition Te3O1410-, which is a new type of finite Te-O oligomer with Te6+ only. The large complex anions form a hexagonal close-packed lattice with the octahedral and tetrahedral interstices being filled with Ca2+ and Na+ cations and water molecules. The octahedral trimers in every other h.c.p. layer rotate around the 31 screw axis for 120°; therefore the unit cell has a very long c axis. This work is one of the few examples of the synthesis of metal tellurates by supercritical hydrothermal techniques.

Two polymorphs of a new barium borate, α- and β-Ba

Three mixed-alkali metals uranyl silicates, Na 3 K 3 [(UO 2 ) 3 (Si 2 O 7 ) 2 ]·2H 2 O ( 1 ), Na 3 Rb 3 [(UO 2 ) 3 (Si 2 O 7 ) 2 ] ( 2 ), and Na 6 Rb 4 [(UO 2 ) 4 Si 12 O 33 ] ( 3 ), have been synthesized by high-temperature, high-pressure hydrothermal reactions at 550 °C and 1440 bar, and characterized by single-crystal X-ray diffraction, photoluminescence, and thermogravimetric analysis. Compound 1 and 2 are isostructural and contain layers of uranyl disilicate. The smaller cation, Na + , is located in the intralayer channels, whereas the larger cations, K + and Rb + , and water molecule are located in the interlayer region. The absence of lattice water in 2 can be understood according to the valence-matching principle. The structure is related to that of a previously reported mixed-valence uranium(V,VI) silicate. Compound 3 adopts a 3D framework structure and contains a unique unbranched dreier fourfold silicate chain with the structural formula {uB,4 1 ∞ }[ 3 Si 12 O 33 ] formed of Q 2 , Q 3 , and Q 4 Si. The connectivity of the Si atoms in the Si 12 O 33 18− anion can be interpreted on the basis of Zintl–Klemm concept. Crystal data for compound 1 : triclinic, P -1, a =5.7981(2) A, b =7.5875(3) A, c =12.8068(5) A, α =103.593(2)°, β =102.879(2)°, γ =90.064(2)°, V =533.00(3) A 3 , Z =1, R 1=0.0278; compound 2 : triclinic, P -1, a =5.7993(3) A, b =7.5745(3) A, c =12.9369(6) A, α =78.265(2)°, β =79.137(2)°, γ =89.936(2)°, V =546.02(4) A 3 , Z =1, R 1=0.0287; compound 3 : monoclinic, C 2/ m , a =23.748(1) A, b =7.3301(3) A, c =15.2556(7) A, β =129.116(2)°, V =2060.4(2) A 3 , Z =2, R 1=0.0304.

Two new barium hydroxyborosilicates, Ba2[Si3B3O12(OH)] (1) and Ba[Si2BO6(OH)] (2), have been synthesized by a flux method at 480 ​°C and characterized by single-crystal X-ray diffraction and infrared spectroscopy. Both compounds have 2D layer structures. Compound 1 contains planar slabs of borosilicate formed of tetrahedral building units which can be described as condensation of three 3-connected 2D single layers with a 63 network topology. The Ba2+ cations are located in both the interlayer and intralayer regions. The structure is unusual with respect to the triple tetrahedral layers. Compound 2 consists of very contorted (3,4)-connected single layers with the rare (42.62)(4.62)2 topology. The single layer is composed of both tertiary and quaternary tetrahedra. The synthesis method is new. A mixture of Ba(OH)2·8H2O, H3BO3 and SiO2 was sealed in a gold ampoule, heated at high temperature in a pressure vessel, and the flux is a small amount of concentrated aqueous hydroxide solution. Crystal data for compound 1: monoclinic, P21/n, a ​= ​4.7112(2) A, b ​= ​29.9482(14) A, c ​= ​7.3773(4) A, β ​= ​92.593(2)°, V ​= ​1039.81(9) A3, Z ​= ​4, and R1 ​= ​0.0246; compound 2: monoclinic, P21/c, a ​= ​7.4206(2) A, b ​= ​8.9405(2) A, c ​= ​8.5677(2) A, β ​= ​90.208(1)°, V ​= ​568.41(2) A3, Z ​= ​4, and R1 ​= ​0.0467.

A new borate fluoride, Ba

A new aluminum borate, Ba[AlB

An organic-inorganic hybrid zinc phosphate with 28-ring channels was synthesized by use of an organic ligand instead of organic amine template under a hydro(solvo)thermal condition. This crystalline zinc phosphate contains large channels constructed from 28 zinc and phosphate tetrahedral units. The walls of the channels consist of two types of zincophosphate chains, in which the Zn atoms are coordinated by 2,4,5-tri(4-pyridyl)-imidazole ligands as pendent groups. This compound exhibits yellow emission and interesting properties of removing cobalt, cadmium, and mercury cations from aqueous solution. A new two-dimensional organic-inorganic hybrid zincophosphate was also obtained by changing the solvent mixture ratios in the synthesis.

The solid solutions (V1–xWx)OPO4 with β-VOPO4 structure type (0.0 ≤ x ≤ 0.01) and αII-VOPO4 structure type (0.04 ≤ x ≤ 0.26) were obtained from mixtures of VVOPO4 and WVOPO4 by conventional solid state reactions and by solution combustion synthesis. Single crystals of up to 3 mm edge length were obtained by chemical vapor transport (CVT) (800 700 °C, Cl2 as a transporting agent). Single crystal structure refinements of crystals at x = 0.10 [a = 6.0503(2) A, c = 4.3618(4) A, R1 = 0.021, wR2 = 0.058, 21 parameters, 344 independent reflections] and x = 0.26 [a = 6.0979(2) A, c = 4.2995(1) A, R1 = 0.030, wR2 = 0.081, 21 parameters, 346 independent reflections] confirm the αII-VOPO4 structure type (P4/n, Z = 2) with mixed occupancy V/W for the metal site. Due to the specific redox behavior of W5+ and V5+, solid solutions (V1–xWx)OPO4 should be formulated as (VIVxVV1–2xWVIx)OPO4. The valence states of vanadium and tungsten are confirmed by XPS measurements. V4+ with d1 configuration was identified by EPR spectroscopy and magnetic measurements. Electronic spectra of the solid solutions show the IVCT(V4+ V5+) and the LMCT(O2– V5+). (V0.74W0.26)OPO4 powders exhibit semi-conducting behavior (Eg = 0.7 eV).

A new uranyl silicate, K2Ca4[(UO2)(Si2O7)2], with a 1D chain structure has been synthesized from a solution of mixed alkali- and alkaline-earth-metal cations under hydrothermal conditions at 550 °C and 1400 bar and characterized by single-crystal X-ray diffraction and photoluminescence spectroscopy. It crystallizes in the triclinic space group P1̅ (No. 2) with a = 6.6354(2) Å, b = 6.6791(2) Å, c = 9.6987(3) Å, α = 98.324(2)°, β = 93.624(2)°, γ = 112.310(2)°, and Z = 1. Its crystal structure consists of a 1D chain of uranyl disilicate formed of corner-sharing UO6 tetragonal bipyramids and Si2O7 double groups. The adjacent chains are separated by K(+) and Ca(2+) cations. It is the first example of uranyl silicate with a 1D chain structure.

Layered vanadyl phosphate hydrates with the V/P ratio of 1:1 represent an important class of low-dimensional phosphate structures as they are of great interest in intercalation chemistry in association with redox catalytic reactions and innovation of light and energy-saving materials. The inorganic layer of VOPO4 is simple chemically, but is actually complex in inner- and inter-layer structures, and can be based on to induce a diversity of new topologies. There have been obstacles in synthesis as to exploring viable synthetic strategy and understanding the structures in depth. This review provides an up-to-date survey to two-dimensional structures based on 4-connected VOPO4 layer. For this, all examples so far reported are investigated and presented, including manipulative synthetic parameters, shared structure features, influence of water content in coordination sphere or as guest, and template size and type effects, control of interlayer spacing, and chemical tailoring the inorganicVOPO4 layer.

A new indium borogermanate incorporating an organic amine ligand, InBGe2O6(OH)2(CH3CH(NH2)CH2NH2)·2H2O, was synthesized under solvothermal conditions and characterized by infrared spectroscopy, thermogravimetric analysis, and emission spectroscopy. This compound is a new example of the combination of metal, boron, and germanium atoms into one structure in the presence of organic amine molecules. Its 2D sheets with one 3-, one 4-, and two types of 6-membered rings consist of In2O6N4 octahedral dimers, Ge2O6(OH) double tetrahedra, and BO3(OH) groups that are interconnected by water molecules to form a 3D supramolecular framework. Interestingly, the emission spectrum for this compound displays a strong broad band centered at 455 nm.

Three-layered zinc phosphites containing single monoamine molecules with different roles have been synthesized using hydro(solvo)thermal methods and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and infrared spectroscopy. Compound 1, (C{sub 8}H{sub 17}NH{sub 3}){sub 4}Zn{sub 3}(HPO{sub 3}){sub 5}·3H{sub 2}O, consists of 20-ring layer structures sandwiched by water molecules and protonated tert-octylamine molecules. The structure of Zn(C{sub 8}H{sub 17}NH{sub 2})(HPO{sub 3}) (compound 2) is composed of 4.8{sup 2} network structures, wherein the tert-octylamines are coordinated to the Zn atom as pendant groups. Compound 3, (C{sub 8}H{sub 17}NH{sub 3}){sub 2}Zn{sub 4}(C{sub 8}H{sub 17}NH{sub 2})(HPO{sub 3}){sub 5}, was prepared in which the amine plays a dual role as both a ligand and a countercation. In addition, compound 1 is the first layered metal phosphite with large 20-ring windows. This group of substances represents the first example of the preparation of compounds in which the reactivity of incorporated single amine molecules is varied by adjusting the synthesis conditions. - Graphical abstract: The first layered metal phosphite with large 20-ring windows, (C8H17NH3)4Zn3(HPO3)5·3H{sub 2}O (1), sandwiched by water molecules and protonated tert-octylamine molecules. Highlights: • The first example of zinc phosphites contains amine molecules with template and ligand roles. • The reactivity of single amine molecules ismore » varied by adjusting the synthesis conditions. • Compound 1 contains the largest pore opening of 20-rings in known layered metal phosphites. • Compound 3 has dual roles of amine molecules in its structure.« less

A salt-inclusion mixed-valence uranium(V,VI) silicate, [Na9F2][(U(V)O2)(U(VI)O2)2(Si2O7)2], was synthesized under hydrothermal conditions at 585 °C and 160 MPa and structurally characterized by powder and single-crystal X-ray diffraction (XRD). The valence states of uranium were established by U 4f X-ray photoelectron spectroscopy (XPS). The structure contains two-dimensional (2D) sheets of uranyl disilicate with the composition [UO2Si2O7], which are connected by U(1)(V)O6 tetragonal bipyramids to form thick layers. The Na(+) cations are located at sites in the intralayer and interlayer regions. In addition to Na(+) cations, the interlayer region also contains F(-) anions such that infinite chains with the formula FNa1/1Na4/2 are formed. The same type of chain was observed in K2SnO3. The title compound is not only the first example of salt-inclusion metal silicate synthesized under high-temperature, high-pressure hydrothermal conditions, as well as the first salt-inclusion mixed-valence uranium silicate, but it is also the first mixed-valence uranium(V,VI) silicate in the literature. Crystal data: [Na9F2][(U(V)O2)(U(VI)O2)2(Si2O7)2], triclinic, P1 (No. 2), a = 5.789(1) A, b = 7.423(2) A, c = 12.092(2) A, α = 90.75(3)°, β = 96.09(3)°, γ = 90.90(3)°, V = 516.5(2) A(3), Z = 1, R1 = 0.0241, and wR2 = 0.0612.

This is the first study on developing six alkali transition metal phosphites as potential candidates of cathode materials grown from molten boric acid, a simple, low energy costing method compared with conventional solid-state reactions. Li2[Mn(HPO3)2] (1) and Li[V(HPO3)2] (2) are featured with high theoretical capacitance values up to 117 and 123 mAh/g, respectively. With the replacement of Li+ by Na+ or K+, four new compounds with strongly related layer topology Na2[Co4(HPO3)5] (3), K2[Co3(HPO3)4] (4), K2[Mn2(HPO3)3] (5), and K[V(HPO3)2] (6) were prepared. The synthesis mediated by molten boric acid automatically provides reductive atmosphere and helps maintain low valence in metal centers.

Two mixed-metal uranium compounds, [Cu(4,4′-bpy)(UO2)0.5(HPO4)(H2PO4)]·H2O (1) and [Cu(4,4′-bpy)(UO2)0.5(HAsO4)(H2AsO4)]·1.5H2O (2) have been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, fluorescence spectroscopy, and magnetic susceptibility. They are the first examples of mixed-metal uranium phosphate and arsenate incorporating an organic ligand. Their structures contain copper uranyl phosphate/arsenate layers which are covalently linked by 4,4′-bpy pillars to form a 3-D framework structure. The fluorescence spectrum of 1 shows the characteristic vibronic structure of the UO22+ moiety despite the presence of copper(II) ions in its structure. The two compounds are isostructural and crystallize in the monoclinic space group C2/c with a=20.184(4) A, b=8.921(2) A, c=19.095(3) A, β=115.15(1)°, and R1=0.0244 for 1, and a=20.184(1) A, b=9.0210(5) A, c=19.714(1) A, β=114.879(1)°, and R1=0.0399 for 2.

The search for new and efficient nonlinear optical (NLO) materials has been an active research because of their technological importance in laser applications. Although a large number of frequency-doubling oxides, phosphates, borates, and fluoride-containing borates were found, no transition-metal silicate with useful NLO properties has been reported. We have now synthesized and grown crystals of two new titanosilicates, Li2K4[(TiO)Si4O12] and Li2Rb4[(TiO)Si4O12], by using a flux and supercritical hydrothermal method. Their unique 3D framework structures contain highly compressed TiO5 square pyramids which are arranged one over the other to form infinite ···Ti-O···Ti-O straight chains with alternating short and long Ti-O distances. These two materials meet the requirements for efficient second harmonic generation including lack of center of inversion symmetry, large susceptibility, phase matching, transmitting at wavelengths of interest, resistant to laser damage, and thermally stable. These attributes make them very attractive for frequency-doubling materials.

The new mixed alkali metal uranyl silicates (V), (VII), and (VIII) are characterized by single crystal XRD.