Search

Lawsonite is a water-rich mineral that has occurred in the geological record since the late Neoproterozoic era. This mineral forms at low-temperature and high- to ultrahigh-pressure conditions in cold subduction zones and has been predicted to be stable down to ca. 300 km. Therefore, lawsonite has been discussed as an essential carrier of water to mantle depths, and its oxygen isotopic composition has been considered a promising tool in characterizing subduction-related fluids down to the deeper upper mantle. In this study, we characterize LM-19 lawsonite in detail as a potential working reference material for oxygen isotopic microanalysis. Multiple LM-19 measurements by secondary ion mass spectrometry reveal that it is homogeneous in oxygen isotopes at the micro-scale. Precise oxygen isotopic analysis by isotope ratio mass spectrometry yields a mean δ18O of 8.98 ± 0.10‰ (1SD) that we recommend as the reference value for the LM-19 lawsonite. This reference material is most suitable for determination of oxygen isotopes in unknown lawsonite samples with low Cr (Cr2O3 <0.3 wt%) and low to moderate total Ti and Fe concentrations (i.e., TiO2 + Fe2O3* <1.36 wt%). The main limitation is that the chemical variability of LM-19 in Ti and Fe may cause a minor matrix effect resulting in the average δ18O bias of −0.30‰ for the regions enriched in total Ti and Fe contents. However, these enriched regions most likely compose only a minor portion of the LM-19 lawsonite (i.e., ca. 20%), meaning that the matrix effect should not significantly affect the accuracy of in situ oxygen isotopic analysis. [ABSTRACT FROM AUTHOR]

Two three-dimensional (3D) porous-layered borates, Na0.5K2.5[AlB7O13(OH)]·H2O (1) and NaKCs[GaB7O13(OH)]·1.5H2O (2), have been obtained under solvothermal conditions. Compound 1 crystallizes in the triclinic space group P1¯, while 2 crystallizes in the monoclinic space group P21/n. Compounds 1 and 2 contain similar units of B7O13(OH) and AlO4/GaO4; the strict alternations of B7O13(OH) clusters and AlO4/GaO4 resulted in 3D open-framework layers with 8-R and 13-R channels along different directions. The shapes and orientations of the channels of 1 and 2 are different due to their different space groups. It's interesting to note that three different alkali metal ions (Na+, K+, and Cs+) are found in different positions in 2. UV-vis diffuse reflectance analysis indicates that both compounds show a wide transparency range with a short-wavelength absorption edge below 190 nm. [ABSTRACT FROM AUTHOR]

Cryo-magnetic coolants based on the magnetocaloric effect (MCE) usually need relatively large fields to achieve practical cooling performance. Thus, it is important to hunt for molecular cryo-magnetic coolants with superior performance of the MCE under low fields (smaller than 2 T), considering the readily attainable low fields from commercialized Nd–Fe–B permanent magnets. In this work, the crystal structure, magnetic susceptibility and isothermal magnetization for two hybrid Gd-complexes, (NH4)[Gd(C2O4)(SO4)(H2O)] (1) and [Gd(C2O4)0.5(CO3)(H2O)] (2), cobridged by organic and inorganic ligands, were solvothermally synthesized and magnetically characterised, with the goal of obtaining novel molecular cryo-magnetic coolants. For 1, the sulfate bridges GdIII ions to generate inorganic chains as supramolecular building blocks (SBBs), which are further connected by the oxalate to result in the final host anionic architecture with an ammonium ion as the guest to balance the charge. For 2, the carbonate bridges GdIII ions to form inorganic layers as SBBs, which are further linked by the oxalate to give birth to the resultant pillar-layer structure. Because the merits of organic oxalate ligands and inorganic ligands (sulfate and carbonate) work together, the resultant compounds show a weak magnetic exchange interaction, a low molecular weight and a dense frame structure, and the observed maximum entropy change (−ΔSmaxm) is up to 42.4 J kg−1 K−1 for 1 at ΔH = 7 T and T = 2 K and 50.7 J kg−1 K−1 for 2 at ΔH = 7 T and T = 4 K, beyond the performance of commercialized gadolinium gallium garnet Gd3Ga5O12 (GGG, −ΔSmaxm = 38.4 J kg−1 K−1 with ΔH = 7 T). Notably, the −ΔSmaxm still reaches 25.2 J kg−1 K−1 for 1 and 26.8 J kg−1 K−1 for 2 at T = 2 K and ΔH = 2 T, and 32.3 J kg−1 K−1 for 1 and 33.3 J kg−1 K−1 for 2 at T = 2 K and ΔH = 3 T, which already outperform GGG (about 24 J kg−1 K−1 with ΔH = 3 T) and make them excellent cryo-magnetic refrigerants for low-temperature applications, even under low external fields. [ABSTRACT FROM AUTHOR]

Two novel photochromic and photomagnetic complexes actuated by nonphotochromic ligands have been hydrothermally synthesized through the pillar-layer strategy. After Xe lamp irradiation at room temperature, compound 1 shows naked-eye detectable photochromism, while 2 exhibits an efficient photodemagnetization effect. [ABSTRACT FROM AUTHOR]

The coordinative linkage of supramolecular zincophosphate building units and an extended dipyridine unit, 1,4-di(pyridine-4-yl)benzene (bpyb), generates two hybrid photochromic frames. The structural and photochromic diversities were mainly attributable to the distinct coordination mode of bpyb in the resultant structure. Different from most of the reported photochromic materials driven by photochromically active units, the crystalline hybrid photochromic materials in this work are decorated by non-photochromic bpyb. The metal-assisted phosphate-to-bpyb charge transfer is responsible for the photochromism. Our work provides a new perspective to develop photochromic hybrid materials based on non-photochromic moieties. [ABSTRACT FROM AUTHOR]

Two zinc-diphosphonates formed from extended dipyridine units di-3,6-(4′-pyridyl)-1,2,4,5-tetrazine (dipytz) and 1,4-di(pyridine-4-yl)benzene (pbyb), [H2-Hdpt][Zn3(HEDP)2(H2O)]·2H2O (1) and [Zn2(HEDP)(pbyb)0.5(H2O)]·H2O (2) were solvothermally prepared (HEDP = 1-hydroxyethylidenediphosphonate, Hdpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole). Compound 1 exhibits an anionic Zn-HEDP layer with protonated dipyridine fragments as the template. In 2, the HEDP ligands bridge Zn2+ ions to form neutral zincophosphonate layers as supramolecular building blocks (SBBs), which are further pillared by neutral pbyb moieties to generate the final 3D pillar-layer structure. Interestingly, in situ reactions have taken place in the formation of 1, and the starting material dipytz in situ transformed to Hdpt in the process of assembly and was captured in the resultant crystal. Although the structural constituents are non-photochromic, 2 features photochromic performance with a detectable color change from colorless to pink under the stimulus of UV light under ambient conditions. A reversible color change process has been realized via annealing the colored sample at 120 °C for half an hour or putting the colored sample in air for two hours. [ABSTRACT FROM AUTHOR]

A pillared-layer strategy is employed to assist the construction of two water-stable Zn-based metal–organic frameworks (MOFs) in this work, [ZnL(Bipy)]·0.5H2O (1) and [ZnL(Bpyb)]·1.5H2O (2) (H2L = 5-(pyridine-4-yl)isophthalic acid, Bipy = 4,4′-bipyridine, and Bpyb = 1,4-bis(pyrid-4-yl)benzene). The linkage of Zn centers and L2− ligands affords the layer structures, which are further pillared by the linear N-donor ligands to the three-dimensional architectures. The “pillars” with diverse molecular lengths lead to different pore sizes in 1 and 2, which show different sorption behaviors for iodine capture. Additionally, the photoluminescence properties of compounds 1 and 2 were investigated. Moreover, the photoluminescence sensing experiment indicates that compound 1 can be considered to be a promising selective sensor for Fe3+. [ABSTRACT FROM AUTHOR]

An innovative and feasible strategy has been explored to prepare stable and highly effective room temperature fluorescence/phosphorescence dual emission materials, in which N-containing organic aromatic structure-directing agents were coordinated to metal phosphite frameworks. [ABSTRACT FROM AUTHOR]

The combination of an electron-rich zinc diphosphonate layer and electron-deficient 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT) generates a 3D inorganic–organic hybrid with an [–ED–EA–ED–EA–] arrangement (ED = electron donor and EA = electron acceptor), which exhibits a wide and rapid photoresponse upon exposure to the stimulus of sunlight, UV light and X-rays at ambient temperature. Notably, the coloration time is 0.1 s when exposed to UV light (320 nm) generated from a Xe-lamp (150 W). [ABSTRACT FROM AUTHOR]

Two zinc-phosphites modified by a rigid amine 3,5-bis(imidazole-1-yl)pyridine (BIP), [Zn2(HPO3)2(BIP)]·H2O (1) and [Zn3(HPO3)3(BIP)(H2O)]·H2O (2), were solvothermally prepared. Compound 1 possesses a zincophosphite layer decorated by BIP moieties via coordinating to intralayer Zn(ii) ions. Compound 2 features a 3D frame with a pillar-layer structure, in which the organic BIP pillars the inorganic zincophosphite layer via coordinating to interlayer Zn(ii) ions. The structural diversity from a 2D layer to a 3D frame was mainly attributable to the different bridging modes of BIP in the process of assembly. Their temperature-dependent photoluminescence properties have also been studied. [ABSTRACT FROM AUTHOR]

Three novel hybrid cuprous halides, [Me3TPT][Cu5I8] (1, Me3TPT = N,N′,N′′-trimethyl-2,4,6-tris(4-pyridyl)-1,3,5-triazine), [Et3TPT][Cu5I8] (2, Et3TPT = N,N′,N′′-triethyl-2,4,6-tris(4-pyridyl)-1,3,5-triazine), and [Me3TPT][Cu5Br8] (3), were solvothermally prepared by using in situ N-alkylated 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT) derivatives as structure-directing agents. All the compounds feature layered structures extended by two types of building units, i.e. the chain-like Cu3I6/Cu3Br7 ({Cu3}) cluster and ribbon-like Cu4I10/Cu4Br10 ({Cu4}) cluster. UV-Vis spectra analyses indicate that they are potential semiconductor materials with narrow energy gaps of 1.05, 1.02, and 1.30 eV, respectively. These materials exhibit stable catalytic activity in the sunlight-driven degradation of organic dyes. Theoretical studies revealed that the N-alkylated TPT moieties contributed to the narrow semiconducting behavior, which results in the excellent visible light-driven photocatalytic activity. [ABSTRACT FROM AUTHOR]

Two zinc-diphosphonates driven by 4,4′-bipyridine (4,4′-bipy), [Zn4(HEDP)2(4,4′-bipy)2]·4.5(H2O) (1) and (H2-4,4′-bipy)0.5·[Zn3(HEDP)(H2EDP)(H2O)]·1.5(H2O) (2), were solvothermally prepared (HEDP = CH3C(OH)(PO3)2, 1-hydroxyethylidenediphosphonate). Compound 1 features a layered structure with the Zn-HEDP chains as supramolecular units and 4,4′-bipy as interchain linkers. Compound 2 possesses a Zn-HEDP layer with protonated 4,4′-bipy as template. The structure differences between the two compounds are mainly ascribed to the distinct role of 4,4′-bipy in the process of in situ assembly. In compound 1, the 4,4′-bipy moiety acts as coordinative unit to participate in the formation of the resulting architecture. However, in compound 2, the protonated 4,4′-bipy serves as template to direct the formation of the final structure. The luminescence and proton conduction of the two compounds were investigated. Compounds 1 and 2 exhibit intense blue fluorescence; compound 2 has a proton conductivity of 2.61 × 10−4 S cm−1 at 100% relative humidity and 70 °C. [ABSTRACT FROM AUTHOR]

A solvothermal reaction of CuI with a bifunctional organic ligand 3,5-pyridinedicarboxylic acid (H2pdc) afforded a novel heterovalent copper–organic framework, [(CuI2I2)CuII4(pdc)4(H2O)4]·4DMSO (1) (DMSO = dimethyl sulfoxide). Compound 1 was structurally characterized by single-crystal X-ray diffraction analyses and further characterized by infrared spectroscopy (IR), powder X-ray diffraction (PXRD), elemental analyses and thermogravimetric analyses (TGA). Structural analysis indicates that two kinds of common secondary building units (SBUs) coexist in this 3D network. The linkage of Cu+ and I− generates [CuI2I2] subunits and the connection of Cu2+ with carboxyl-O atoms gives rise to binuclear paddle-wheel [CuII2(COO)4(H2O)2] moieties. In compound 1, two different SBUs are bridged with pdc2− ligands to construct a micro-sized cage with an internal spherical cavity. Through a cage-to-cage connection, the 3D porous framework is formed which features intersecting 1D channels. Gas sorption measurements were conducted on the activated 1, showing a H2 uptake of 1.46 wt% at 77 K and under 1 bar with a high initial adsorption enthalpy of 8.2 kJ mol−1. Moreover, compound 1 has excellent adsorption selectivity for CO2 over N2 and CH4. [ABSTRACT FROM AUTHOR]

Two isostructural lanthanide (Ln) hybrid complexes co-bridged by organic oxalate and inorganic hypophosphite, [Ln(oxa)(H2PO2)(H2O)2] (oxa = oxalate; Ln = Gd (1), Dy (2)), were solvothermally prepared with the goal of elucidating the role of a hybrid framework in the generation of novel molecular magnetic materials. The title compounds feature a two dimensional (2D) hybrid layer. The LnIII ions are octa-coordinated with distorted square antiprism geometry. The adjacent LnIII ions are co-bridged by hypophosphite and one type of oxalate ligand to form 1D hybrid chains, which are further linked by a second type of oxalate ligand to generate the resulting 2D framework. Magnetic investigations reveal that compound 1 features a large magnetocaloric effect with −ΔSmaxm = 46.60 J kg−1 K−1 (134.39 mJ cm−3 K−1), due to the combined advantages of organic oxalate and inorganic hypophosphite ligands, while compound 2 displays slow magnetic relaxation. [ABSTRACT FROM AUTHOR]

A zinc diphosphonate with protonated 2,4,6-tri(4-pyridyl)-1,3,5-triazine (H3TPT) as the template was hydrothermally prepared. The host layered framework was composed of 1-hydroxyethylidenediphosphonate and zinc ions. The guest H3TPT locates between the adjacent layers, acting as the charge balancer and template. The title compound features rapid photochromism upon irradiation with sunlight or UV light at ambient temperature. [ABSTRACT FROM AUTHOR]

Two isostructural transition-metal (TM) triphosphonates decorated with neutral rigid N-containing ligands 1,3,5-tris(1-imidazolyl)benzene (tib), [Zn3(L1)(tib)]·8H2O (1) and [Co3(L1)(tib)]·9H2O (2) (H6L1 = N(CH2PO3H2)3), nitrilotris(methylenephosphonic acid), have been solvothermally prepared and structurally characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis and single-crystal/powder X-ray diffraction. The title compounds exhibit a pillar-layer structure with the TM-triphosphonates as layers and the rigid tib ligand as a pillar. The luminescence and magnetic properties have been investigated. Compound 1 exhibits intense blue luminescence, while compound 2 shows weak ferromagnetic behaviour. [ABSTRACT FROM AUTHOR]

A novel open-framework beryllium phosphite, [H4tren][Be6(HPO3)8]·(H2O)3 (1, tren = tris(2-aminoethyl)amine), was synthesized under solvothermal conditions. Its structure features a 3D interrupted network with a low density (1.594 g cm−3), and 1 represents the first example of a beryllium phosphite material with extra-large 18-ring channels. [ABSTRACT FROM AUTHOR]

A pillared-layer strategy is employed to assist the construction of two water-stable Zn-based metal–organic frameworks (MOFs) in this work, [ZnL(Bipy)]·0.5H2O (1) and [ZnL(Bpyb)]·1.5H2O (2) (H2L = 5-(pyridine-4-yl)isophthalic acid, Bipy = 4,4′-bipyridine, and Bpyb = 1,4-bis(pyrid-4-yl)benzene). The linkage of Zn centers and L2− ligands affords the layer structures, which are further pillared by the linear N-donor ligands to the three-dimensional architectures. The “pillars” with diverse molecular lengths lead to different pore sizes in 1 and 2, which show different sorption behaviors for iodine capture. Additionally, the photoluminescence properties of compounds 1 and 2 were investigated. Moreover, the photoluminescence sensing experiment indicates that compound 1 can be considered to be a promising selective sensor for Fe3+. [ABSTRACT FROM AUTHOR]

Two zinc-diphosphonates formed from extended dipyridine units di-3,6-(4'-pyridyl)-1,2,4,5-tetrazine (dipytz) and 1,4-di(pyridine-4-yl)benzene (pbyb), [H2-Hdpt][Zn3(HEDP)2(H2O)]·2H2O (1) and [Zn2(HEDP)(pbyb)0.5(H2O)]·H2O (2) were solvothermally prepared (HEDP = 1-hydroxyethylidenediphosphonate, Hdpt = 1H-3,5-bis(4-pyridyl)-1,2,4-triazole). Compound 1 exhibits an anionic Zn-HEDP layer with protonated dipyridine fragments as the template. In 2, the HEDP ligands bridge Zn2+ ions to form neutral zincophosphonate layers as supramolecular building blocks (SBBs), which are further pillared by neutral pbyb moieties to generate the final 3D pillar-layer structure. Interestingly, in situ reactions have taken place in the formation of 1, and the starting material dipytz in situ transformed to Hdpt in the process of assembly and was captured in the resultant crystal. Although the structural constituents are non-photochromic, 2 features photochromic performance with a detectable color change from colorless to pink under the stimulus of UV light under ambient conditions. A reversible color change process has been realized via annealing the colored sample at 120 °C for half an hour or putting the colored sample in air for two hours.

A pillared-layer strategy is employed to assist the construction of two water-stable Zn-based metal-organic frameworks (MOFs) in this work, [ZnL(Bipy)]·0.5H2O (1) and [ZnL(Bpyb)]·1.5H2O (2) (H2L = 5-(pyridine-4-yl)isophthalic acid, Bipy = 4,4'-bipyridine, and Bpyb = 1,4-bis(pyrid-4-yl)benzene). The linkage of Zn centers and L2- ligands affords the layer structures, which are further pillared by the linear N-donor ligands to the three-dimensional architectures. The "pillars" with diverse molecular lengths lead to different pore sizes in 1 and 2, which show different sorption behaviors for iodine capture. Additionally, the photoluminescence properties of compounds 1 and 2 were investigated. Moreover, the photoluminescence sensing experiment indicates that compound 1 can be considered to be a promising selective sensor for Fe3+.

Two zinc-phosphites modified by a rigid amine 3,5-bis(imidazole-1-yl)pyridine (BIP), [Zn2(HPO3)2(BIP)]·H2O (1) and [Zn3(HPO3)3(BIP)(H2O)]·H2O (2), were solvothermally prepared. Compound 1 possesses a zincophosphite layer decorated by BIP moieties via coordinating to intralayer Zn(ii) ions. Compound 2 features a 3D frame with a pillar-layer structure, in which the organic BIP pillars the inorganic zincophosphite layer via coordinating to interlayer Zn(ii) ions. The structural diversity from a 2D layer to a 3D frame was mainly attributable to the different bridging modes of BIP in the process of assembly. Their temperature-dependent photoluminescence properties have also been studied.

Three novel hybrid cuprous halides, [Me3TPT][Cu5I8] (1, Me3TPT = N,N',N''-trimethyl-2,4,6-tris(4-pyridyl)-1,3,5-triazine), [Et3TPT][Cu5I8] (2, Et3TPT = N,N',N''-triethyl-2,4,6-tris(4-pyridyl)-1,3,5-triazine), and [Me3TPT][Cu5Br8] (3), were solvothermally prepared by using in situ N-alkylated 2,4,6-tri(4-pyridyl)-1,3,5-triazine (TPT) derivatives as structure-directing agents. All the compounds feature layered structures extended by two types of building units, i.e. the chain-like Cu3I6/Cu3Br7 ({Cu3}) cluster and ribbon-like Cu4I10/Cu4Br10 ({Cu4}) cluster. UV-Vis spectra analyses indicate that they are potential semiconductor materials with narrow energy gaps of 1.05, 1.02, and 1.30 eV, respectively. These materials exhibit stable catalytic activity in the sunlight-driven degradation of organic dyes. Theoretical studies revealed that the N-alkylated TPT moieties contributed to the narrow semiconducting behavior, which results in the excellent visible light-driven photocatalytic activity.

Two zinc-diphosphonates driven by 4,4'-bipyridine (4,4'-bipy), [Zn 4 (HEDP) 2 (4,4'-bipy) 2 ]·4.5(H 2 O) (1) and (H 2 -4,4'-bipy) 0.5 ·[Zn 3 (HEDP)(H 2 EDP)(H 2 O)]·1.5(H 2 O) (2), were solvothermally prepared (HEDP = CH 3 C(OH)(PO 3 ) 2 , 1-hydroxyethylidenediphosphonate). Compound 1 features a layered structure with the Zn-HEDP chains as supramolecular units and 4,4'-bipy as interchain linkers. Compound 2 possesses a Zn-HEDP layer with protonated 4,4'-bipy as template. The structure differences between the two compounds are mainly ascribed to the distinct role of 4,4'-bipy in the process of in situ assembly. In compound 1, the 4,4'-bipy moiety acts as coordinative unit to participate in the formation of the resulting architecture. However, in compound 2, the protonated 4,4'-bipy serves as template to direct the formation of the final structure. The luminescence and proton conduction of the two compounds were investigated. Compounds 1 and 2 exhibit intense blue fluorescence; compound 2 has a proton conductivity of 2.61 × 10 -4 S cm -1 at 100% relative humidity and 70 °C.

A solvothermal reaction of CuI with a bifunctional organic ligand 3,5-pyridinedicarboxylic acid (H 2 pdc) afforded a novel heterovalent copper-organic framework, [(CuI 2 )Cu(pdc) 4 (H 2 O) 4 ]·4DMSO (1) (DMSO = dimethyl sulfoxide). Compound 1 was structurally characterized by single-crystal X-ray diffraction analyses and further characterized by infrared spectroscopy (IR), powder X-ray diffraction (PXRD), elemental analyses and thermogravimetric analyses (TGA). Structural analysis indicates that two kinds of common secondary building units (SBUs) coexist in this 3D network. The linkage of Cu + and I - generates [CuI 2 ] subunits and the connection of Cu 2+ with carboxyl-O atoms gives rise to binuclear paddle-wheel [Cu(COO) 4 (H 2 O) 2 ] moieties. In compound 1, two different SBUs are bridged with pdc 2- ligands to construct a micro-sized cage with an internal spherical cavity. Through a cage-to-cage connection, the 3D porous framework is formed which features intersecting 1D channels. Gas sorption measurements were conducted on the activated 1, showing a H 2 uptake of 1.46 wt% at 77 K and under 1 bar with a high initial adsorption enthalpy of 8.2 kJ mol -1 . Moreover, compound 1 has excellent adsorption selectivity for CO 2 over N 2 and CH 4 .

A novel aluminoborate (NH(4))(6)[C(5)NH(12)](6)[Al(12)B(65)O(105)(OH)(33)]·(H(2)O)(15) (QD-6), has been synthesized under mild hydrothermal conditions and characterized by IR, elemental analysis, TGA, powder and single-crystal X-ray diffractions. This compound crystallizes in the rhombohedral space group R3 (No. 148) with the lattice constants a = 23.7421(2) Å, c = 24.7699(3) Å, V = 12091.9(2) Å(3), and Z = 3. QD-6 consists of two unprecedented aluminoborate clusters, [Al(6)B(34)O(54)(OH)(18)](6-) and [Al(6)B(31)O(51)(OH)(15)](6-), which are built from the same hexagon-like [B@Al(6)O(24)] clusters and [B(11)O(17)(OH)(6)] or [B(10)O(16)(OH)(5)] polyborates.