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Four inorganic-organic hybrid borates, K[B6O9(OH)(en)]·H2O (1, en = ethylenediamine), K[B6O9(OH)(1,3-dap)]·H2O (2, 1,3-dap = 1,3-diaminopropane), K[B6O9(OH)(1,6-dah)0.5]·H2O (3, 1,6-dah = 1,6-diaminlhexane) and [(1,3-dap)Cd@B5O8(OH)]·0.5H2O (4), were made under solvothermal conditions. 1 and 2 are isostructural and feature a 2D layer built by B6O9(OH) clusters and modified by en and 1,3-dap via B-N-C linkages. By replacing en and 1,3-dap with longer and more flexible 1,6-dah, a new type of oxoboron cluster organic framework 3 was obtained, which was composed of the same B6O9(OH) cluster layers as in 1 and 2 and 1,6-dah linkers. By replacing alkali metal K with transition metal Cd under similar synthetic conditions, another type of oxoboron cluster organic framework 4 was made in which the Cd-centered wheel cluster layers and 1,3-dap linkers were connected via Cd-N-C linkages.

Two new layered and porous-layered borates ([H2dap][B7O11(OH)] (1, dap = 1,2-propanediamine) and [H3O]K3.52Na3.48{Al2[B7O13(OH)][B5O10][B3O5]}[CO3] (2)) have been solvothermally made. 1 features a 2D layer made of the [B7O13(OH)]6- cluster, in which H2dap is located in the windows of the layers. The fundamental building block (FBB) [B7O13(OH)]6- cluster in 1 represents a new type of FBB of the hepta-borate family. 2 is a novel aluminoborate with a 3D porous-layered structure formed by three types of oxoboron clusters, [B7O13(OH)]6-, [B5O10]5- and [B3O7]5-, respectively. The strict alternation of the different oxoboron clusters and AlO4 tetrahedra leads to the abundant channel systems of the structure. 2 is the first aluminoborate (ABO) containing three types of oxoboron clusters and the first 3D porous-layered ABO with seven types of channels. UV-vis diffuse reflectance spectra reveal that both of them are wide band-gap semiconductors and have potential applications in UV regions.

Solvothermal reactions of V-shaped ligand 1,1′-(oxybis(1,4-phenylene))-bis(1H-1,2,4-triazole) (OPBT) with deprotonated phthalic acid (H2PA) or (1,1′-biphenyl)-4,4′-dicarboxylic acid (H2BDA) in the presence of transition metal nitrates in N,N-dimethylformamide/water (DMF/H2O) solvent system yielded five new complexes: [Cu5(μ3-OH)2(OPBT)2(PA)4]n (1), [Cd2(OPBT)(PA)2]n (2), {[Zn(OPBT)(PA)]·H2O}n (3), [Cd(μ2-H2O)(OPBT)(BDA)]n (4), and [Co(OPBT)2(BDA)]n (5). Complexes 1 and 2 show two-dimensional (2D) layers based on one-dimensional (1D) infinite rod second building units (SBUs) of pentanuclear Cu(II) or tetranuclear Cd(II) clusters with OPBT ligands, which are further formed into three-dimensional (3D) supramolecular frameworks by interlayer hydrogen bonding or π···π stacking interactions, respectively. Complex 3 displays a 1D chain, which is further extended into a 3D supramolecular structure through C–H···π and hydrogen bonding interactions. Complex 4 features a 2D layer with the sql topology, which is furt...

The partial replacement of Ge atoms in tetrahedral positions by a small number of B atoms leads to a new microporous borogermanate, CsBxGe6–xO12 (x = 1), under solvothermal conditions. Its framework shows the highest atomic ratios of Ge/B in reported borogermanates and leads to a new type of zeolite sodalite-type net.

A novel 3D aluminoborate with [Zn(H2O)4]2+ cationic complexes as structure-directing agents (SDAs), namely, [Zn(H2O)4][Al(B5O10)]·0.5(H2O) (1), has been solvothermally prepared and characterized by IR spectroscopy, UV–vis reflection spectroscopy, thermogravimetric (TG) analyses, powder and single crystal X-ray diffraction, respectively. The alternative linkage of AlO4 tetrahedra and B5O10 units produces an open-framework aluminoborate with helical 6- and 8-membered ring (MR) channels, as well as large odd 11-MR channels. The [Zn(H2O)4]2+ templates, generated in situ from solvothermal conditions, are orderly located in the center of the 11-MR channels. The second-harmonic generation (SHG) measurement indicates that 1 exhibits about 0.5 times that of KDP standard (K2HPO4).

Two inorganic–organic hybrid borates, [Zn(en)2{B8O11(OH)4}] (1, en = ethylenediamine) and [Cd(TREN){B8O11(OH)4}] (2, TREN = tris(2-aminoethyl)amine) have been made under hydro(solvo)thermal conditions and characterized by IR spectroscopy, elemental analysis, single crystal X-ray diffraction, diffuse-reflectance spectroscopy, thermogravimetric analyses, and powder X-ray diffraction. Crystal data for 1: triclinic, P−1, a = 8.7091(5) A, b = 8.8731(2) A, c = 12.7642(8) A, α = 87.042(4)°, β = 78.198(5)°, γ = 80.816(4)°, V = 952.96(9) A3. Crystal data for 2: monoclinic, P21/c, a = 11.5051(4) A, b = 8.7879(4) A, c = 19.9322(7) A, β = 91.433(3)°, V = 2014.63(14) A3. They both contain [B8O11(OH)4]2− cluster units, which linked each other to form 1-D chains. These 1-D chains are further joined together to produce 3-D supramolecular frameworks via H-bonding interactions. Interestingly, the [B8O11(OH)4]2− cluster in 1 is made of [B5O8(OH)2]3− and [B3O5(OH)2]2− sub-cluster units with two O atoms in common, while in 2 consists of [B5O7(OH)3]2− and [B3O6(OH)]4− sub-cluster units with two O atoms in common. The [B8O11(OH)4]2− ligands in 1 and 2 are coordinated to the supporting metal complexes in different ways. The anion in 1 is coordinated to the Zn(en)2 by a terminal OH group whereas the anion in 2 is coordinated by a bridging O atom. The in situ organic rearrangement reaction from triethylene tetramine (TETA) to tris(2-aminoethyl)amine (TREN) has been observed in the formation of 2.

By performing first-principles calculation, we studied the interface of transition metal dichalcogenides MX2 (M = Mo, W; X = S, Se) monolayer on Al2O3(0 0 0 1) substrate for applications in field effect transistor. We firstly examined the 1H, 1T and ZT phases of MX2 monolayers and found that the 1H structure is the best channel material among the three polytypes of MX2. 1H MX2 on both the Al and O terminated Al2O3(0 0 0 1) substrate are energetically favorable. Systems of MX2 on Al-terminated Al2O3(0 0 0 1) substrate have larger band gaps than the counterpart of O-terminated Al2O3(0 0 0 1) substrate. More importantly, WS2 on Al-terminated Al2O3(0 0 0 1) substrate is the most stable one and has a direct band gap of 1.79 eV. Furthermore, we investigated the effect of intrinsic defects on the electronic properties of WS2/Al2O3(0 0 0 1) interface. Our calculation results show that Al, W, S vacancy exhibit p-type doping and n-type doping is obtained for O vacancy, and all of these vacancy defects induce defect states in the band gap for both the Al terminated and O terminated WS2/Al2O3 systems.

Molecular models of polynorbornene homopolymers, with POSS (polyhedral oligomeric silsesquioxane) group linked to the side chain via various numbers of methylene spacers, were constructed and named as P-m-POSS (where m represents the number of methylene units that connect amide and POSS end group on the side chain, m = 0, 4, and 9), respectively. By molecular mechanics (MM) and molecular dynamics (MD) simulation methods, molecular geometry, chain mobility and packing characteristics were investigated to elucidate the complex interplay of intrachain and interchain in homopolymers dependent on various methylene spacer lengths of the side chain. With short spacer length containing less number of methylene units, the synergetic mobility of the main chain and the side chain can be observed in P-0-POSS by analysis of mean square displacement (MSD), denoting an intrachain coupling restraint within molecule. It is also noticed that the disorganization of twisted side chains surrounding the main chain results in a loose and irregular packing in P-0-POSS, validated by the amorphous morphology in experiment. As the spacer length increased with more methylene units in P-4-POSS, side chains with the highest mobility are partially stretched and independent of the main chain, suggesting the invalidation of intrachain coupling restraint. Furthermore, with the longest spacer length containing 9 methylene units, fully stretched side chains are decoupled from the main chain and have a tendency to be close to each other in P-9-POSS. The interchain correlation between side chains in P-9-POSS facilitates a distinctively regular interdigitation in bulk structure, resulting in the highest crystallinity in experiment.

Under hydrothermal conditions, replacement of the water molecules in the [Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](8+) cluster of mixed-valent Mn6 sandwiched silicotungstate [(B-α-SiW9 O34 )2 Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](12-) (1 a) with organic N ligands led to the isolation of five organic-inorganic hybrid, Mn6 -substituted polyoxometalates (POMs) 2-6. They were all structurally characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, diffuse-reflectance spectroscopy, and powder and single-crystal X-ray diffraction. Compounds 2-6 represent the first series of mixed-valent {Mn(III) 4 Mn(II) 2 O4 (H2 O)4-n (L)n } sandwiched POMs covalently functionalized by organic ligands. The preparation of 1-6 not only indicates that the double-cubane {Mn(III) 4 Mn(II) 2 O4 (H2 O)4-n (L)n } clusters are very stable fragments in both conventional aqueous solution and hydrothermal systems and that organic functionalization of the [Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](8+) cluster by substitution reactions is feasible, but also demonstrates that hydrothermal environments can promote and facilitate the occurrence of this substitution reaction. This work confirms that hydrothermal synthesis is effective for making novel mixed-valent POMs substituted with transition-metal (TM) clusters by combining lacunary Keggin precursors with TM cations and tunable organic ligands. Furthermore, magnetic measurements reveal that 3 and 6 exhibit single-molecule magnet behavior.

Using reticular chemistry allowed the design and construction of four novel Zn(II)/Cd(II) coordination polymers, {[Zn(BTPA)(TPA)]·H2O}n (1), {[Zn(TTPA)(TPA)]·H2O}n (2), {[Cd2(TTPA)2(TPA)2(DMF)]·2H2O}n (3), and {[Cd(TTPBDA)(TPA)]0.5·DMF·H2O}n (4). They were successfully synthesized from bi-, tri-, and tetratopic phenylamine derivatives (BTPA = bis(4-(1H-1,2,4-triazol-1-yl)phenyl)amine, TTPA = tris(4-(1H-1,2,4-triazol-1-yl)phenyl)amine, TTPBDA = N4,N4,N4′,N4′-tetrakis(4-(1H-1,2,4-triazol-1-yl)phenyl)-(1,1′-biphenyl)-4,4′-diamine) incorporating a linear terephthalic acid (H2TPA) ligand and Zn(II)/Cd(II) nitrate salts. These transparent crystals present gradually increasing dimensionality and complexity upon extension of the denticity of the phenylamine organic building blocks, as clearly supported by single-crystal X-ray analysis, infrared spectroscopy, elemental analysis, powder X-ray diffraction, and thermogravimetric analysis. Complex 1 shows two-dimensional (2D) threefold-interpenetrating layers (2D + 2D...

By the hydrothermal technique, a series of organic–inorganic hybrid polyoxometalates (POMs) Hx(H2en)y [Fe2Ln(β-PW10O37)2(Tart)]·nH2O (Ln = La3+, (x, y, n) = (5, 3, 9) for 1; Ln = Ce3+, (x, y, n) = (5, 3, 7) for 2; Ln = Sm3+, (x, y, n) = (3, 4, 25) for 3; Ln = Tb3+, (x, y, n) = (3, 4, 21) for 4; H2Tart = tartaric acid) have been obtained and structurally characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses and single-crystal X-ray diffraction. The common structural characteristics of 1–4 consist of a [Fe2Ln(β-PW10O37)2(Tart)]9− unit, in which transition metal and lanthanide ions co-exist in the vacant site of divacant [β-PW10O37]9− with the assistance of Tart ligands. It should be pointed out that 1–4 represent the first 3d–4f heterometallic cluster sandwiched phosphotungstate dimers, [Fe2Ln(β-PW10O37)2(Tart)]9−, linked by Fe–O–Ln–O–Fe bonds. Furthermore, 3 and 4 exist as rare supramolecular nanotubes built from the organic–inorganic hybrid 3d–4f POM units. Also, the photochromism and optical properties of 1–4 have been studied.

Two organic-inorganic hybrid pillared-layer lanthanide borates, [Ln2B8O12(bdc)3(H2O)]·H2O (Ln = Pr, 1; Nd, 2; H2bdc = 1,4-benzene dicarboxylic acid), have been made, in which inorganic layers are built by Ln-centred oxoboron ring clusters, Ln@B12O28/Ln@B12O29, while the pillars are organic bdc linkers. Interestingly, two types of linkages, Ln-O-C and B-O-C bonds, exist in the structures, showing firstly novel linking modes between inorganic polyborate and organic dicarboxylate.

Two new metal borates, K[B7O9(OH)5]·Hen (1, en = enthylenediamine) and Na2Cs4Ba2[B12O18(OH)6]·4(OH) (2) have been synthesized under solvothermal conditions. Their structures were determined by the single crystal X-ray diffraction and were further characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and powder X-ray diffraction, respectively. 1 crystallizes in the triclinic system, P-1 space group, a = 7.7152(6), b = 8.4057(6), c = 12.1319(10) A, α = 92.505(6), β = 98.944(7), γ = 103.825(6)°, Z = 2. 2 crystallizes in the orthorhombic system, Pmn21 space group, a = 12.6972(6) A, b = 13.7037(6) A, c = 9.4968(5) A, Z = 2. Compound 1 consists of isolated [B7O9(OH)5]2− clusters which are held together through H-bonding interactions and K atoms to form a 3-D supramolecular framework. For 2, bowl-like isolated [B12O18(OH)6]6− clusters were linked together to form a 3-D framework by different metal ions and H-bond system.

A new mixed metal borate, NaPb4(H2O)(B5O9)2·BO3, with an acentric structure has been successfully made under hydrothermal conditions and structurally characterized by IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction, respectively. The structural analysis shows that 1 crystallizes in the orthorhombic space group Pnn2 (No. 34) with a = 11.3724(5) A, b = 11.4455(4) A, c = 6.5578(2) A and Z = 2. In the structure 1, the structural building unit, B5O12 cluster, connects adjacent six same ones to form a 3-D oxoboron framework with 8-membered ring (MR) and 10-MR channels along the c-axis. The Pb atoms and coordinated water molecules are located in the 8-MR channels, while the 10-MR channels were occupied by the chains built by Na atoms and the BO3 groups. Second-harmonic generation (SHG) measurements on the powder samples reveal that 1 exhibits SHG efficiency approximately 2 times that of KH2PO4 (KDP). Also it has a UV cutoff edge below 220 nm.

An open-framework borate [Zn(H2O)4][B6O10] with acentric structure, has been successfully obtained for the first time under solvothermal conditions. It has been characterized by powder and single crystal X-ray diffraction, IR spectroscopy, diffuse-reflectance spectroscopy and thermogravimetric (TG) analyses, respectively. It crystallizes in the orthorhombic system, space group Pna21, a = 11.3140(6) A, b = 11.8995(7) A, c = 8.6140(5) A and Z = 4. In the structure, the alternative connections between [B3O7] units give rise to an unprecedented 3D borate framework with 11- and 10-MR channels, in which the [Zn(H2O)4]2+ complexes are located. It has a cut-off edge below 200 nm and exhibits second harmonic generation (SHG) efficiency approximately 0.4 times that of KH2PO4 (KDP).

Two new pentaborate clusters, [MPD][B5O6(OH)4] (1, MPD = 2-methyl-1,4,5,6-tetrahydropyrimidine-3-ium) and SrB5O8(OH) H2O (2), have been hydro(solvo)thermally synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray structural analysis, respectively. Crystal data for 1: monoclinic, P21/c, a = 9.3384(3) A, b = 17.3774(5) A, c = 9.1886(3) A, β = 93.172(3)°, Z = 4. Crystal data for 2: triclinic, P-1, a = 6.6406(6) A, b = 6.6784(8) A, c = 10.2162(15) A, α = 98.905(11)°, β = 92.237(9)°, γ = 119.446(11)°, Z = 2. In compound 1, all the terminal O atoms of [B5O6(OH)4]− clusters are hydroxyl groups, which hinder the further connection of the [B5O6(OH)4]− clusters, only forming 3-D supramolecular frameworks via extensive hydrogen-bonding interactions. In compound 2, the [B5O10(OH)]6− clusters link each other to form a 2-D layer, which are further extended to 3-D supramolecular frameworks via extensive hydrogen-bonding interactions. Interestingly, a novel in situ organic reaction between 1,3-diaminoprapane and CH3COO− group has been observed during the formation of compound 1.

Two new tetraborates, namely [Li(H2O)4]2[Cu(H2O)6][Cu(H2O)5]2[B4O5(OH)4]4·4H2O (1) and [Cu(en)2(H2O)2][Cu(en)2(B(OH)3)2][B4O5(OH)4]2·H2O (2) have been made under solvothermal conditions and characterized by FT-IR spectroscopy, powder X-ray diffraction, single crystal X-ray diffraction and thermogravimetric analysis, respectively. 1: triclinic, Pī, a = 7.0400(2) A, b = 7.8779(3) A, c = 25.8958(11) A, α = 90.827(3)o, β = 95.985(3)o, γ = 105.816(3)o, Z = 1. 2: monoclinic, P2/c, a = 12.5723(6) A, b = 9.1508(5) A, c = 15.9800(6) A, β = 94.742(4)o, Z = 2. In structure 1, the B4O5(OH)4 clusters join together via H-bonding interactions to produce 3-D supramolecular framework with three types of channels located by the Cu(H2O)6, Cu(H2O)5 and Li(H2O)4 polyhedra, respectively. While in 2, the B4O5(OH)4 clusters link each other to form 2-D layers and then further pillared by Cu(en)2(B(OH)3)2 complexes via H-bonding interactions, resulting in 3-D supramolecular framework with hexagonal and rectangle channels, in which the rectangle channels are filled by Cu(H2O)2(en)2 complexes.

Two new mixed metal borates, Li2[Mg(B6O7(OH)6)2]·2H2O (1) and Li4Ca2[B8O12(OH)4]2·3H2O (2) have been made under solvothermal conditions and characterized by FT-IR spectroscopy, powder X-ray diffraction, single crystal X-ray diffraction and thermogravimetric analysis, respectively. Crystal data for 1: triclinic, \({P_{\bar 1}}\), a = 6.9415(4) A, b = 9.1626(5) A, c = 9.4540(6) A, α = 71.697(6)o, β = 88.431(5)o, γ = 68.409(5)o, Z = 1. Crystal data for 2: monoclinic, C2/c, a = 19.8507(5) A, b = 6.7560(2) A, c = 20.0454(5) A, β = 93.985(2)o, Z = 4. In structure 1, the structural building unit (SBU), sandwich type [Mg(B6O7(OH)6)2]2−, connects adjacent six same ones to form a 2-D layer via Li-based polyhedra in the bc plane and further link by hydrogen bonding to form 3-D supramolecular network. In the structure 2, the SBUs, [B8O14(OH)4]8−, link together to produce a 2-D layer with 13-membered ring (MR) windows along the bc-plane. Such layers are further linked by Li-based polyhedra to form a 3-D framework.

Six new cobalt(ii) metal-organic frameworks, {[Co1.5(TTPA)(BTC)(H2O)]2·13H2O}n (1), [Co(TTPA)(PA)]n (2), {[Co(TTPA)(BDA)0.5(NO3)]·3H2O}n (3), {[Co2(TTPA)3(OBA)2(H2O)3]·2CH3CN·4H2O}n (4), {[Co(TTPA)(AIP)(H2O)]·2H2O}n (5), and {[Co(TTPA)(MIP)(H2O)]·2H2O}n (6), have been prepared by the self-assembly of a tris(4-(1H-1,2,4-triazol-1-yl)phenyl)amine (TTPA) ligand with different aromatic carboxylate auxiliary ligands (H3BTC = 1,3,5-benzenetricarboxylic acid, H2PA = phthalic acid, H2BDA = (1,1'-biphenyl)-4,4'-dicarboxylic acid, H2OBA = 4,4'-oxydibenzoic acid, H2AIP = 5-aminoisophthalic acid, H2MIP = 5-methylisophthalic acid) and cobalt salts. Their structures have been characterized by infrared spectroscopy, elemental analysis, single crystal X-ray analysis, and powder X-ray diffraction. Complex 1 is an unusual 4-nodal (3,3,4,8)-connected three-dimensional (3D) new topological net with the point symbol of (4·6·8)4(4(4)·6(7)·8(15)·10(2))(6(2)·8(4)). Complex 2 has a 2-fold interpenetrating 3D dia framework. Complex 3 displays a rare binodal (3,4)-connected 4-fold interpenetrating 3D architecture with a fsc-3,4-C2/c topology with the point symbol of (4·6·8)(4·6(2)·8(3)). Complex 4 shows two distinct two-dimensional (2D) layers with hcb topologies, which are further packed into a 3D structure by O-HO hydrogen bonding interactions. Both complexes 5 and 6 feature similar 2D sheets with sql topologies, which can be further packed into a 3D structure by O-HO hydrogen bonding interactions. Moreover, the thermal stability and UV-visible spectra of these complexes are also discussed in detail. Meanwhile, the variable-temperature magnetic susceptibility measurement of complex 1 reveals antiferromagnetic interactions between Co(ii) ions.

SmCo 6.6 Nb 0.4 nanoflakes with TbCu 7 structure were successfully prepared by surfactant-assisted high energy ball milling (SA-HEBM) with heptane and oleic acid as milling medium. The microstructure, crystal structure and magnetic properties were studied by scanning electron microscopy, X-ray diffraction, and vibrating sample magnetometer, respectively. The effects of ball milling time on the c -axis crystallographic alignment and coercivity of the nanoflakes were systematically investigated. The research showed that the nanoflakes had an average thickness of 100 nm, an average diameter of 1 μm, with an aspect ratio as high as 100. As the ball milling time increased from 2 to 8 h, the reflection peaks intensity ratio I (002) / I (101) , which indicated the degree of c -axis crystal texture of the SmCo 6.6 Nb 0.4 phase, increased first, reached a peak at 4 h, and then decreased. Meanwhile, the coercivity of the nanoflakes also increased first, reached a peak at 13.86 kOe for 4 h, and then decreased.

Six new lanthanide (Ln) germanate cluster organic frameworks (LnGeCOFs) derived from {Ln8Ge12} cage cluster units {[Nd(pza)2(H2O)] [Nd8Ge12(μ3-O)24E12(pza)(H2O)12]}·3H2O (1), {[Dy(CH3COO)(CO3)(H2O)]2[Dy8Ge12(μ3-O)24E12(H2O)12]}·11H2O (2), {[TbGeE(HO)2O(pza) (H2O)]2[Tb8Ge12(μ3-O)24E12(H2O)6]}·18H2O (3), {[DyGeE(HO)2O(C3H5NO2)(H2O)]2[Dy8Ge12(μ3-O)24E12(H2O)8]}·8H2O (4), {[Tb(pca)2 (H2O)]3[Tb8Ge12(μ3-O)24E12(H2O)4]}·(OH)3·10H2O (5) and {[Dy(pza)2(H2O)][Dy(pza)2(H2O)2][Dy(pza)3(H2O)][Dy8Ge12(μ3-O)24E12(pza)(HCOO) (H2O)6]}·5H2O (6) have been hydrothermally synthesized and structurally characterized. Increasing the amount of the second ligands can induce not only the assembly from 1 to 5, 6 based on Ln oxides as the starting sources, but also the assembly from 2 to 3, 4 based on Ln salts as the starting sources. The successful preparation of these LnGeCOFs suggests the importance of the second ligands in the structural construction of 1–6. To our knowledge, 1 is the first example that includes right- and left-handed helical chains among LnGeCOFs based on bis(carboxyethylgermanium)sesquioxide. 2, 4 and 6 are the first dysprosium incorporated organogermanates based on bis(carboxyethylgermanium)sesquioxide. 4 and 5 display very open framework structures with a solvent-accessible volume of 34.6% for 4 and 35.0% for 5. Moreover, the solid-state photoluminescence properties of 1, 3 and 5 have been investigated at room temperature and they exhibit the characteristic emission bands derived from Ln cations.

A series of open-framework aluminoborates (ABOs), namely, [Zn2(en)5][Al2B10O20] (1), [Zn(en)(dien)][AlB5O10] (2), [Zn(en)3][AlB7O12 (OH)2] (3), [Zn(en)2][AlB5O10] (4), K7{AlO0.5[BO2(OH)]Zn@[B12O21(OH)3]}⋅H2O (5) (en=ethylenediamine, dien=diethylenetriamine) have been made under mild solvothermal conditions and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, IR and UV/Vis spectroscopy, thermogravimetric analysis, and nonlinear optical determination. They were classified as two types: Compounds 1–4 contain intersecting channels and exhibit various 4-connected nets built by AlO4 tetrahedra and oxo boron clusters, zinc–amine complexes act as the templates (1–3) or directly bond to the walls of the ABO (4); compound 5 exhibits a double-layer structure made by nanosized [BO2(OH)]Zn@[B12O21(OH)3] ({BZn@B12}) clusters with Al2O7 dimers, the channels are within the layer. The second harmonic generation (SHG) measurement shows that the SHG responses of 1–3 are about 2.5, 1.6, and 0.5 times that of KH2PO4. Compounds 1–2 are type I phase-matchable materials. UV/Vis spectroscopy indicates that compounds 1–5 are wide-band-gap semiconductors.

Six new coordination compounds, namely [Co(H2bptc)]n (1), [Mn(H2bptc)]n (2), [Cd2(bptc)(phen)2(H2O)2]n (3), [Eu2(cpa)3(DMF)2]n (4), [Nd2(cpa)3(DMF)2]n (5) and [Pr2(cpa)3(DMF)2]n (6) (bptc4− = biphenyl-2,2′,4,4′-tetracarboxylate anion, phen=1,10-phenanthroline, cpa2− = 4-chloroisophthalic acid anion) were synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra, and thermogravimetric analysis. Co and Mn compounds are isostructural, and possess a three-dimensional 5, 5-connected network. In Cd compound, multicarboxylate ligand H4bptc link Cd centers to generate a two-dimensional 4, 4-c net structure with phen acting as terminal ligand. Eu, Nd, and Pr compounds have similar structures, and cpa2− ligands link lanthanide cations to generate a two-dimensional sheet structure. Magnetic susceptibility measurements indicate that the Co compound has a dominating ferromagnetic coupling between Co(II) ions, and Mn compound exhibits antiferromagnetic coupling between Mn(II) ions. Furthermore, their luminescent properties are also determined in the solid state at room temperature.

The aggregation structure of a novel polyimide (PIM-6) with six methylene flexible spacing groups in biphenyl side chain synthesized by the traditional two-step imidisation process was investigated by polarized light microscope (PLM), small angle X-ray scattering (SAXS), wide angle X-ray scattering (WAXS), and molecular simulation approach. The agreement between the experimental data and simulation result reveals that due to the predominant interchain interaction, each three backbones stack together to form a distinct lamellar cluster with side chains packed inside dispersedly. The thickness of the lamellar cluster is about 16.0 A°, corresponding to a strong peak at 5.5° in SAXS pattern. As the backbone is not perfectly parallel to each other in each lamellar cluster, the distance between each backbone ranges from 5.8 to 8.8 A° possibly relating to the weak peak at 9.8° in WAXS pattern. Meanwhile, no birefringence or apparent phase texture has been observed by PLM indicating an amorphous nature in this film. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010

Five new coordination compounds, namely [Zn(Hbtc)(1,3-bix)(H2O)]n (1), {Zn2(µ-O)(btc)(timp)]·3(H2O)}n (2), {[Zn3(4,4′-bibp)2(btc)2(H2O)2]·4(H2O)}n (3), {[Ni3(4,4′-bibp)2(btc)2(H2O)2]·3(H2O)}n (4), {[Cu3(4,4′-bibp)2(btc)2(H2O)]·2(H2O)}n (5), where 1,3 - bix = 1- (3 - (1H -inidazol - 1 − yl)methyl)benzyl)-1H-imidazole, timp = 1- (3,5-di (1H-imidazol-1-yl)phenyl)-1H-imidazole, 4,4′-bibp = 4,4′-bisimidazolylbiphenyl, and btc = 1,3,5-benzenetricarboxylate anion, were synthesized under hydrothermal conditions. In compound 1, both 1,3-bix ligand and btc anion act as bidentate bridging ligands, and connect the zinc cations into a one-dimensional chain. In compound 2, timp and btc anions as tridentate ligands coordinate to zinc cations to form a three-dimensional 3,6-connected network. Compounds 3–5 have similar structures, 4,4′-bibp and btc anions act as bidentate and tetradentate ligands, respectively, and coordinate to metal cations to form a three dimensional 4,4-connected network. The luminescence properties for 1–3 and magnetic properties for 4–5 are also discussed in detail.

Four new lanthanide complexes, [Nd(4-Pyta)3(H2O)2] n (1), [Ce(4-Pyta)3(H2O)2] n (2), [Eu(4-Pyta)3(H2O)2] n (3) and [Gd(4-Pyta)3(H2O)2] n (4), have been obtained from reaction of lanthanide(III) nitrate with 4-Pyta (4-pyridylthioacetate) in water. Their structures were characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. The crystals belong to triclinic, space group P 1 and all complexes exhibit one-dimensional chains that arrange to form a three-dimensional supramolecular architecture by hydrogen bonds between the chains.

The combination of metal ions with H3tbba has resulted in the formation of two three dimensional coordination compounds {[Zn(H2tbba)2(H2O)] · 2(OC3H6)} n (1) and {[Mn(H2tbba)2(H2O)] · 2(OC3H6)} n (2) (H2tbba = 2-thiobarbituric acid anion). Compounds 1 and 2 are isostructural with metal ions bridged by four hydroxyl oxygens from four different H2tbba ligands to form a 3D network. H2tbba exhibits bidentate coordination with both hydroxyl oxygens participating in coordination, a new coordination mode. Nonlinear absorption and refraction of 1 and 2 in DMF are studied by using Z-scan measurement technique at 532 nm. 1 and 2 possess nonlinear optical absorption and self-focusing.

A mixed-ligand compound, [Ni2(BPTC)(pyz) · 2H2O] n (0.5H2O) n (BPTC = 3,3′,4, 4′-benzophenone-tetracarboxylate, pyz = pyrazine), has been prepared hydrothermally by assembly of BPTC, NiCl2·6H2O and pyz. X-ray diffraction analysis of a single crystal reveals the three-dimensional framework assembled from pyz-pillared two-dimensional sheets. Three types of channels in one direction are established inside the structure. The third-order nonlinear optical (NLO) properties in DMF have been studied by Z-scan technique using an 8 ns laser at 532 nm. The results reveal that the new compound exhibits strong NLO absorption and self-focusing refractive performance (n 2 = 2.7 × 10−17 m2 W−1).

In our early research, the experiment of three synthesized polyimides (PP0DA-PI, PP2DA-PI and PP6DA-PI) with different methylene spacing groups in biphenyl side chain but with the same backbone reveals that the PP6DA-PI with six methylene flexible spacing groups in biphenyl side chain has lower intrinsic viscosity, density and glass transition temperature than those of the PP0DA-PI without methylene spacing group and PP2DA-PI with two methylene spacing groups in biphenyl side chains but keeps the mechanical property to that of the PP0DA-PI and PP2DA-PI. The aim of this paper is to explain the addition of the methylene spacing groups leading to the diversity of polyimide’s properties; molecular mechanics and molecular dynamics techniques were adapted to generate reasonable molecular models to establish the structure–property relationship of polyimide. Lots of interesting results have been obtained as follows. The modeling of chain conformation shows that the biphenyl side groups in PP0DA-PI are almost vertical to the backbone, whereas the biphenyl side groups in PP6DA-PI are almost parallel to the backbone indicating that PP6DA-PI exhibits a strong intra-chain interaction leading to in situ reinforcement interaction between the main chain and the side chain validated by the charge density, dipole moment and force current property of the two phenyls in biphenyl side chains. For this reinforcement in PP6DA-PI, the original modulus has been enhanced to some extent. Meanwhile, though the PP6DA would be more reactive due to higher charge density on N atom of the diamine monomer, the bulk structure of the side chain hindering the polymerization approach of the monomers leads to lower intrinsic viscosity of PP6DA-PAA. The density of PP6DA-PI does not decrease excessively with respect to the increase in chain length because of the bended side chain in this system. Furthermore, using conformational grid scan, potential energy contour map illuminates that the addition of the methylene spacing group in biphenyl side chain decreases the energy barrier in synchronous rotational bonds of the backbone resulting in lower glass transition temperature of PP6DA-PI.

A series of open-framework aluminoborates (ABOs), namely, [Zn2 (en)5 ][Al2 B10 O20 ] (1), [Zn(en)(dien)][AlB5 O10 ] (2), [Zn(en)3 ][AlB7 O12 (OH)2 ] (3), [Zn(en)2 ][AlB5 O10 ] (4), K7 {AlO0.5 [BO2 (OH)]Zn@[B12 O21 (OH)3 ]}⋅H2 O (5) (en=ethylenediamine, dien=diethylenetriamine) have been made under mild solvothermal conditions and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, IR and UV/Vis spectroscopy, thermogravimetric analysis, and nonlinear optical determination. They were classified as two types: Compounds 1-4 contain intersecting channels and exhibit various 4-connected nets built by AlO4 tetrahedra and oxo boron clusters, zinc-amine complexes act as the templates (1-3) or directly bond to the walls of the ABO (4); compound 5 exhibits a double-layer structure made by nanosized [BO2 (OH)]Zn@[B12 O21 (OH)3 ] ({BZn@B12 }) clusters with Al2 O7 dimers, the channels are within the layer. The second harmonic generation (SHG) measurement shows that the SHG responses of 1-3 are about 2.5, 1.6, and 0.5 times that of KH2 PO4 . Compounds 1-2 are type I phase-matchable materials. UV/Vis spectroscopy indicates that compounds 1-5 are wide-band-gap semiconductors.

The aggregation structure of a novel polyimide (PI-6) with six methylene flexible spacing groups in biphenyl side chain was investigated using polarized optical microscope (POM), wide/small-angle X-ray diffraction (WAXD/SAXD) and molecular simulation approach. Depending on increasing temperature, the sandwich layer aggregation structure of PI-6 was developed from the thermo reversible gel. The backbones are lamellar stacking with 11.5 A thickness. The side chains are randomly packed into the backbone lamellar intervals and the width of this layer for both backbone and side chain is about 23.1 A which is consistent with the simulation data.

The self-assembly reaction of the preformed clusters with two extended linear and trigonal rigid ligands as organic linkers afforded two 2D and 3D Mo(W)/Cu/S-based cluster polymers. They show unprecedented structure types in Mo(W)/S/Cu chemistry and exhibit strong third-order nonlinear optical properties.

Five metal-organic frameworks (MOFs) formed by [WS(4)Cu(x)](x-2) secondary building units (SBUs) and multi-pyridyl ligands are presented. The [WS(4)Cu(x)](x-2) SBUs function as network vertexes showing various geometries and connectivities. Compound 1 contains one-dimensional channels formed in fourfold interpenetrating diamondoid networks with a hexanuclear [WS(4)Cu(5)](3+) unit as SBU, which shows square-pyramidal geometry and acts as a tetrahedral node. Compound 2 contains brick-wall-like layer also with a hexanuclear [WS(4)Cu(5)](3+) unit as SBU. The [WS(4)Cu(5)](3+) unit in 2 is a new type of [WS(4)Cu(x)](x-2) cluster unit in which the five Cu(+) ions are in one plane with the W atom, forming a planar unit. Compound 3 shows a nanotubular structure with a pentanuclear [WS(4)Cu(4)](2+) unit as SBU, which is saddle-shaped and acts as a tetrahedral node. Compound 4 contains large cages formed between two interpenetrated (10,3)-a networks also with a pentanuclear [WS(4)Cu(4)](2+) unit acting as a triangular node. The [WS(4)Cu(4)](2+) unit in 4 is isomeric to that in 3 and first observed in a MOF. Compound 5 contains zigzag chains with a tetrahedral [WS(4)Cu(3)](+) unit as SBU, which acts as a V-shaped connector. The influence of synthesis conditions including temperature, ligand, anions of Cu(I) salts, and the ratio of [NH(4)](2)WS(4) to Cu(I) salt on the formation of these [WS(4)Cu(x)](x-2)-based MOFs were also studied. Porous MOF 3 is stable upon removal and exchange of the solvent guests, and when accommodating different solvent molecules, it exhibits specific colors depending on the polarity of incorporated solvent, that is, it shows a rare solvatochromic effect and has interesting prospects in sensing applications.

The self-assembly of 3,5-pyrazoledicarboxylic acid (H3pdc) and metal salts under hydrothermal conditions leads to the formation of a series of novel NaI-CuII-LnIII heterometallic coordination polymers, [[Na(H2O)4]2[Cu(pdc)2Ln(H2O)5]2 x 3H2O]n [Ln = La (1); Sm (2); Pr (3); Nd (4) and pdc3- = 3,5-pyrazoledicarboxylate]. X-Ray structure analyses show that these complexes all exhibit pairs of infinite, unexpected, cationic and anionic chains. It is the first successful attempt to construct unprecedented NaI-CuII-LnIII heterometallic coordination polymers with both infinite cationic and anionic chains. These four complexes show homologous thermal stabilities. The different magnetic properties of are also been reported in this paper.

In the title compound, C19H12N2O3, the 1-benzofuro[3,2-d]pyrimidinone unit is approximately planar, the maximum deviation from the mean plane being 0.045 (1) Å. The attached phenyl ring makes a dihedral angle of 86.73 (6)° with the fused ring system. The packing of the molecules in the crystal structure is mainly governed by C—H...π hydrogen-bonding interactions.