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Trivalent lanthanide (Ln3+)‐doped hollow upconversion nanocrystals (UCNCs) usually exhibit unique optical performance that cannot be realized in their solid counterparts, and thus have been receiving tremendous interest from their fundamentals to diverse applications. However, all currently available Ln3+‐doped UCNCs are solid in appearance, the preparation of hollow UCNCs remains nearly untouched hitherto. Herein, a class of UCNCs based on Yb3+/Er3+‐doped tetralithium zirconium octafluoride (Li4ZrF8:Yb/Er) featuring 2D layered crystal lattice is reported, which makes the fabrication of hollow UCNCs with a peasecod‐like shape possible after Ln3+ doping. By employing the first‐principle calculations, the unique peasecod‐like hollow nanoarchitecture primarily associated with the hetero‐valence Yb3+/Er3+ doping into the 2D layered crystal lattice of Li4ZrF8 matrix is revealed. Benefiting from this hollow nanoarchitecture, the resulting Li4ZrF8:Yb/Er UCNCs exhibit an abnormal green upconversion luminescence in terms of the population ratio between two thermally coupled states (2H11/2 and 4S3/2) of Er3+ relative to their solid Li2ZrF6:Yb/Er counterparts, thereby allowing to prepare the first family of hollow Ln3+‐doped UCNCs as supersensitive luminescent nanothermometer with almost the widest temperature sensing range (123–800 K). These findings described here unambiguously pave a new way to fabricate hollow Ln3+‐doped UCNCs for numerous applications., A class of peasecod‐like hollow Yb3+/Er3+‐doped Li4ZrF8 upconverting nanocrystals (UCNCs) that features a 2D layered crystal lattice is reported. Abnormal green upconverting luminescence that cannot be achieved in the solid UCNCs is observed in these peasecod‐like hollow UCNCs, thereby making them suitable as supersensitive nanothermometers with a wide temperature range for optical temperature sensing.

A local structure around lanthanide (Ln3+) emitters in Ln3+-doped upconversion nanocrystals (UCNCs) is of fundamental importance in tailoring their upconversion luminescence (UCL) features. However, a general strategy responsible for the local-structure-dependent UCL in Ln3+-doped UCNCs has not been conclusively established to date. Herein, we report a new class of alkaline zirconium fluoride-based Yb3+/Er3+ co-doped UCNCs featuring a diversity of crystallographic structures for Ln3+ ion doping, which thereby allow us to thoroughly understand the origin underlying the local-structure-dependent UCL of the Er3+ ion for the first time. We reveal that the high-symmetry crystal lattice of Yb3+/Er3+ co-doped UCNCs may incur the large UCL red-to-green intensity ratio of Er3+ regardless of their identical elemental compositions. In combination with the first-principles calculations, we show that such local-structure-dependent UCL of Er3+ is primarily due to the varied electronic band structures induced by the Yb3+/Er3+ doping in different crystallographic structures of alkaline zirconium fluorides. These findings may open up a new avenue for constructing high-quality UCNCs with a tailored UCL profile and lifetime for diverse applications.

Three new coordination polymers [Zn(Htip)Cl(H2O)]n (1), [Zn(Htip)2]n (2) and [Cd(Htip)2]n·2nH2O (3) were synthesized by reactions of Zn(II)/Cd(II) salts with a multidentate tetrazole-based ligand 2-(4-(tetrazol-5-yl)phenyl)imidazo(4,5-f)(1,10)phenanthroline (H2tip). Complex 1 possesses an infinite 1D coordination chain, and further forms the final 3D supramolecule through π⋯π stacking interactions. Complexes 2 and 3 are isomorphous, and both of them feature an 8-fold interpenetrating 4-connected 3D framework with the dia topological net and the Schlafli symbol of {66}. In 1–3, the Htip− ligand links two metal centers through three terminal N-donors. The structural analyses indicate that the anions and solvents can subtly influence the formation of the resulting network. Moreover, the thermal stabilities and photoluminescent properties of 1–3 are investigated in the solid state.

Five d10 transition-metal clusters, {[Zn15(2,6-Hbptp)(2,6-bptp)7(μ2-O)4(μ2-OH)4(HCOO)2(NO3)(H2O)2]·20H2O} (1), {[Zn8(2,6-Hbptp)(2,6-bptp)5(μ3-O)2]·(ClO4)·7H2O} (2), {[Cd8(2,6-Hbptp)2(2,6-bptp)4(μ3-O)2]·(NO3)2·10H2O} (3), {[Ag7(2,6-Hbptp)(2,6-bptp)3]·4H2O·CH3OH}n (4), and {[Ag6(2,6-Hbptp)2(2,6-bptp)2][Ag6(2,6-Hbptp)2(2,6-bptp)2]2·30H2O·4CH3OH} (5), based on bent ligand 2,6-bis[3-(pyrazin-2-yl)-1,2,4-triazolyl]pyridine (2,6-H2bptp) have been synthesized. Compound 1 exhibits a novel fanlike Zn15 cluster, which is the highest-nuclearity Zn cluster with 2,6-H2bptp reported thus far. In 2 or 3 (M = Zn/Cd), each ligand coordinates to three M2+ ions, to form an M8L6 cluster. The structure of compound 4 is a Ag6 cluster-based 1D chain, where each hexanuclear [Ag6(2,6-Hbptp)(2,6-bptp)3]− cluster links its equivalent ones via sharing the Ag atom. Compound 5 contains two kinds of Ag6 clusters, and the alternating arrangement of them gives the final structure. It is worth mentioning that the Ag–Ag bond distances in 4 ...

Four indium(III)-biphenyl carboxylate coordination complexes: [In(dpdc)(bipy)Cl]2 (1), {[In(Hdptc)(bipy)]2·H2O}n (2), [In(dptc)·H3O]n (3), [In3(μ2-OH)2(Hdptc)(dptc)H2O]n (4) (H2dpdc = diphenyl-2,2′-dicarboxylic acid, bipy = 2,2′-bipyridine, H4dptc = biphenyl-2,2′,6,6′-tetracarboxylic acid) have been synthesized under hydrothermal and solvothermal conditions. Complex 1 exhibits a dimeric molecule structure featuring a square motif organized by two In(III) ions and two dpdc ligands each at the corner; 2 contains a similar dimeric segment which is extended into a 1D ribbon structure by the Hdptc ligands and further assembled into 2D supramolecular layer through hydrogen bonding; 3 features a 2D (4,4) grid layer, which is assembled into 3D supramolecular network through hydrogen bonding with guest water molecules. Complex 4 consists of an unprecedented eight-connected trinuclear In3(μ2-O)2(CO2)8 building unit which is jointed by four-connected dptc ligand into a binodal (4,8)-connected scu topology. The results present a feasible way of manipulation to control the dimensionality of the complexes by adjusting ligands and reaction temperatures. The complexes are also characterized by X-ray powder diffractions (PXRD), infrared spectroscopy and elemental analysis.

Solvothermal reactions of 2,2′-biphenyldicarboxylate (H2dpa) and 4,4′-azobispyridine (azpy) in the presence of transition metal ions produce six new complexes, namely, [Co(dpa)(bphy)]n (1), [Co(dpa)(azpy)(H2O)]n·0.5nH2O (2), [Zn(dpa)(bphy)]n (3), [Zn(dpa)(azpy)(H2O)]n (4), [Mn(dpa)(azpy)(H2O)]n·0.5nH2O (5), and [Mn(dpa)(azpy)]n·nH2O·nMeOH (6) (bphy = 1,2-bis(4-pyridyl)hydrazine). The crystal structure analyses reveal that complexes 1 and 3 are isostructural which features a plywood-like structure, while complex 4 exhibits a parallel chains array. Complexes 2 and 5 afford a two-dimensional chiral (4,4) network, and complex 6 shows a (4,4) network. It was noteworthy that the in situ reduction of azpy to bphy was found in complexes 1 and 3, which were confirmed by single-crystal structures and LC-MS analyses. However, this in situ reduction was not found at a low reaction temperature in the syntheses of complexes 2, 4, and 5. The second-harmonic-generation (SHG) properties of 1 and 3 and the solid circular d...

Treatment of bix (1, 4-bis(imidazole-1-ylmethyl)benzene) with AgI generated [(Ag4I4)(bix)]n 1, whose crystal structure reveals a 2D organic–inorganic layer formed by novel wave-like silver(I) iodide chains with the linkers of bix ligands. The layers are arranged in parallel with the mode of {ABAB…} type showing 1D rectangular channels. In solid state, 1 exhibits multiple emission properties originating from its different natures, while optical absorption spectrum suggests that 1 might be a potential wide-gap semiconductor.

Two novel compounds, [Zn(H2PIDC)2(H2O)2] (1) and [Zn4(PIDC)2(SO4)(H2O)5]·(2.5H2O) (2) (H3PIDC = 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylic acid) have been synthesized under hydrothermal condition, and characterized by thermal analyses (TGA), powder X-ray diffractions (PXRD), and single-crystal X-ray diffractions, respectively. Compound 1 is constructed from mononuclear molecules which form the 2D square networks and further extend to 3D supermolecular framework through the π–π stacking and strong hydrogen bonding interactions. Compound 2 exhibits a 3D framework and generates the 1D open rhombic channels filled with the coordinated water molecules, sulfate anions and free water molecules. The structure of 2 can be rationalized as a (4,4,4)-connected net and shown as a unique (4.53.6.7)4(42.52.72)2(52.62.72) topology. The different luminescent nature for 1 and 2 may be due to their various delocalization environments.

Four nickel(II)-5-aminodiacetic isophthalate coordination polymers with different auxiliary ligands are synthesized by the solvothermal method. {[Ni4(adip)2(H2O)10]·6H2O}n (1) (H4adip = 5-aminodiacetic isophthalic acid) is a supermolecular structure assembled by two-dimensional (2D) layers, and it can be viewed as a novel binodal (3,4)-connected topological net with a Schlafli symbol of (4.6.8)4(62.82.102) which has not been reported in the literature. When dipyridyl auxiliary ligands with different spacers are engaged in the reactions to pillar the 2D layers of 1, the 3D frameworks of complexes 2–4 are obtained. {[Ni3(Hadip)2(bpy)2(H2O)4]·9H2O}n (2) (bpy = 4,4′-bipyridine) was crystallographically characterized to be a three-dimensional (3D) coordination network with SPC519 type topology. {[Ni8(adip)4(bpy)(H2O)18]·10H2O}n (3) as a 3D framework exhibits a scarcely reported (3,5)-connected topology with a Schlafli symbol of (4.6.8)4(62.86.102). {[Ni2(adip)(bpp)(H2O)2]·2H2O}n (4) (bpp = 1,3-bis (4-pyridyl)p...

A series of novel three-dimensional (3D) 3d-4f heterometallic coordination complexes, [{LnZn(bpdc)2(OAc)(H2O)2}·H2O]n (Ln = Nd (1), Sm (2), Eu (3), Tb (4), Dy (5), Er (6); H2bpdc = 2,2′-bipyridyl-4,4′-dicarboxylic acid; HOAc = acetic acid), have been successfully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. All complexes are isostructural and display new 2-fold interpenetrating (3,6)-connected network topology. The luminescent properties of 1–5 in the solid state at room temperature have been studied in detail. It is the first series of luminescent 3d-4f heterometallic complexes with bpdc2– ligands, and it has been found that the energy transitions from the ligands to Eu3+ and Tb3+ are more effective than those to Sm3+ and Nd3+, and the energy transition from the ligand to Dy3+ is in between. Furthermore, thermogravimetric analysis and powder X-ray diffraction are also investigated.

Tripodal host 2,4,6-tris(1-phenyl-1H-tetrazolylsulfanylmethyl)mesitylene (TPTM) has been synthesized through a facile procedure. As expected, it adopts an all-syn cylindrical configuration, thereby delimiting an inner cavity. To explore the solvatomorphism and inclusion behavior of TPTM, a series of organic and inorganic species were employed as guests to afford 17 inclusion compounds (1, 2, 3 a-3 f, 4 a-4 i) that can be classified into four distinct forms (forms I-IV), under similar conditions. These compounds were characterized by single-crystal and powder X-ray diffraction, and (1)H NMR studies. In compound 1 with form I, one foot of a TPTM molecule inserts into the cavity of an opposite TPTM molecule to form a dimeric "hand-shake" motif with one acetonitrile molecule occupying the void. Compound 2 with form II contains three types of capsule-shaped dimers, each of which holds a CH(2)Cl(2) molecule as the guest. In compounds 3 a-3 f with form III, each pair of TPTM molecules interdigitates to form a capsule-shaped dimeric unit accommodating a guest molecule in the endo-cavity. In compounds 4 a-4 i with form IV, each TPTM molecule makes contact with three nearby TPTM molecules in a "self-including" manner to generate a graphite-like organic layer, and through further superposition to form open hexagonal channels. From the experimental and theoretical results, the intrinsic properties of guest molecules, such as size, shape, and self-interaction, can be regarded as the main factors leading to these solvatomorphism phenomena and the subtle inclusion behavior of TPTM. Thermogravimetric analyses show that the encapsulated guest molecules in these compounds can be evacuated at relatively high temperatures, and this demonstrates the outstanding inclusion capability of TPTM. In addition, for compound 4 a with benzene molecules in the channels, reversible exchange of toluene and separation of xylene isomers on single crystals have been observed.

[Co3(1,2-S2C6H4)3(PPh3)3][CoBr3(DMF)]sol (1, sol=CHCl3·O(C2H5)2·H2O) was obtained from the reaction of CoBr(PPh3)3 with Na2(S2C6H4) in chloroform. The Co3 core in the cation of 1 exhibits a metal-metal bonded isosceles triangle, in which the two longer Co—Co bonds are both bridged by S2C6H4 ligands on two sides of the triangle plane respectively, while the bottom short Co—Co bond is bridged by the third bidentate S2C6H4 ligand. A series of polynuclear cobalt cluster compounds with phosphine, thiolate and/or sulphur ligands were prepared by low oxidation state Co+ with thiolates in organic solvents. These tri-, tetra-, hexa-, heptanuclear cluster compounds 1–8 with various types of crystal structures can be viewed as the condensed polynuclear cobalt complexes that the cobalt atom frameworks with sulphur bridged were built through the small triangular units of [Co3S3nL3] (n=1,2) with or without [CoL] (L=PR3, Br, Cl,5-C5H5) fragments.

[V2(μ-S2)2(S2CNEt2)4] 2CH3Cl was synthesized by the reaction of NaS2CNEt2, Li2S and VOCl3 at room temperature. Crystal data: M= 1061.3, space group Pbca, with the orthorhombic parameters: a=20.123(3), b = 20.485(4)1c=10.911(3)A, V=4497.7A3, Z=4, Dc=1.57 g/cm3, Mo Ko radiation (λ=0.71069 A), μ = 13.2 cm−1, F(000)—2168. Final R = 0.041 and Rw=0.047 for 2288 observed reflections with I>3σ(I). The coordination sphere of each V atom in title compound is a distorted tetragonal prism composed of two bidentate dithiocarbamate and two S21− ligands. The V—V distance is 2.890 A while the V—S distances fall in the range of 2.422–2.505 A.

Two isomeric Au complexes, [Au(Stt)Cl]n (1) and [Au(Stt)Cl]4n (2) (Stt = S-trithiane), have been prepared and structurally and spectroscopically characterized. Each compound crystallizes as a unique form with aurophilic interactions between the linear and two-coordinated Au(I) cations. In complex 1, the Au(Stt)Cl molecules self-associate to form 1D nearly linear chains via equivalent aurophilic interactions, whereas the structure of complex 2 features 1D flexural chains composed of zigzag [Au(Stt)Cl]4 tetramers through varying aurophilic interactions. Emission spectra of both complexes at room temperature give strong red luminescence.

A novel In(III) coordination complex, [In(ptc)(H2O)]n (H3ptc = 4,4′,4″-phosphoryltribenzoic acid) (1), was synthesized under hydrothermal condition and characterized by single-crystal X-ray analysis, IR, X-ray powder diffraction (XRD), thermogravimetric analysis (TGA) and solid-state photoluminescence. Complex 1 crystallizes in a chiral P21 space group, In(III) ions are eight-coordinated and the ligand exhibits a novel and unique tetrahedral coordination mode. The complex shows intense blue emission at 435 nm with the excitation of 330 nm.

Assembly of 5-sulfosalicylic acid (H{sub 3}L) and d{sup 10} transition metal ions (Cd{sup II}, Ag{sup I}) with the neutral N-donor ligands produces five new complexes: [Cd{sub 2}(HL){sub 2}(4,4'-bipy){sub 3}]{sub n}.2nH{sub 2}O (1), {l_brace}[Cd{sub 2}(mu{sub 2}-HCO{sub 2}){sub 2}(4,4'-bipy){sub 2}(H{sub 2}O){sub 4}][Cd(HL){sub 2}(4,4'-bipy)(H{sub 2}O){sub 2}]{r_brace}{sub n} (2), {l_brace}[Cd(4,4'-bipy)(H{sub 2}O){sub 4}][HL].H{sub 2}O{r_brace}{sub n} (3), [Cd(HL)(dpp){sub 2}(H{sub 2}O)]{sub n}.4nH{sub 2}O (4), {l_brace}[Ag(4,4'-bipy)][Hhbs]{r_brace}{sub n} (5) (4,4'-bipy=4,4'-bipyridine, dpp=1,3-di(pyridin-4-yl)propane, H{sub 2}hbs=4-hydroxybenzenesulfonic acid, the decarboxylation product of H{sub 3}L). Complex 1 adopts a 5-connected 3D bilayer topology. Complex 2 has the herring-bone and ladder chain, which are extended to a 3D network via hydrogen bonding. In 3-4 complexes, 3 is a 3D supermolecular structure formed by polymeric chains and 2D network of HL{sup 2-}, while 4 gives the double-stranded chains. In 5, ladder arrays are stacked with the 2D networks of Hhbs{sup -} anions in an -ABAB- sequence. Complexes 1-4 display green luminescences in solid state at room temperature, while emission spectra of 3 and 4 show obvious blue-shifts at low temperature. - Graphical abstract: Reactions of 5-sulfosalicylic acid (H{sub 3}L) and d{sup 10} metal ions (Cd{sup II}, Ag{sup I}) produce five new complexes. Complexes 1-4 all display green luminescences at room temperature.

Reactions of 2,2′-dihydroxyl-[1,1′]-binaphthalene-3,3′-dicarboxylate acid (H2bna) with manganese chloride by a solvent or solvothermal method in the presence of pyridine (py) or 4-picoline (pic) give birth to three 1D to 3D frameworks: [Mn(bna)(DMF)2(H2O)2]n·nDMF (1), {(Hpic)2[Mn3(bna)4(C2H5OH)2(H2O)2]·5H2O}n (2), and {(Hpy)2[Mn3(bna)4(py)2(H2O)2]·4H2O}n (3) (DMF = N,N′-dimethylformamide). Crystal structure analyses reveal that 1 is a mesomer with equivalent R- and L-helical rectangular tubes constructed from homochiral ligands, which is further assembled into a 3D supramolecular network through hydrogen bonds and C−H···π interactions. Complex 2 consists of a (4,4) grid chiral layer structure, while 3 features a 3D cubic diamond network with Schlafli symbol 66 topology, though they both comprise of [Mn3(μ2-COO)6(COO)2] pinwheel molecular building blocks which act as 4-connected nodes and bna2− as linkers. Magnetic studies indicate that antiferromagnetic couplings exist in both 2 and 3.

The reaction of 2,2′-bipyrazine (bpz) and Cu(NO3)2 with addition of HCl gave a new complex [Cu5(bpz)2Cl10(H2O)] n · nH2O, with bpz serving as a µ 3-ligand to link three different copper centers. X-ray crystallography shows a self-assembled supermolecule formed by [Cu5(bpz)2] repeating unit further bridged through Cl−. This is the first Cu(bpz) complex which possesses extended topology instead of closure. Magnetic susceptibility measurements for this complex from 2 to 300 K reveal weak antiferromagnetic interactions between copper(II) in agreement with out-of-plane exchange pathways and large Cu–Cu separation.

Two novel In(III) complexes, [In(bna)(Hbna)]n (1) and [In2(bna)2(μ2-OH)2]n·4nH2O (2) (H2bna=2,2′-dihydroxy-1,1′-binaphthyl-3,3′-dicarboxylate acid), have been reported. Complex 1 adopts a 2D layer structure, where each layer composed from homochiral ligands is chiral while the ligands in two neighboring layers are enantiomer. Complex 2 is constructed by individual –In–O–In– chains, which are further connected by bna2− into a 3D honeycomb framework. As a derivative of H2bna ligand, dmbna (3) was recrystallized for structurally comparison with 1-2 (dmbna=dimethyl 2,2′-dihydroxy-1,1′-binaphthyl-3,3′-dicarboxylate). X-ray powder diffractions (XRD) and thermogravimetric analyses (TGA) for 1-2 show that they are highly thermally stable in the solid state. Complexes 1 and 2 exhibit the intense yellow luminescence at 573 nm and blue luminescence at 459 nm at room temperature, respectively. And an astonishing blue shift of 105 nm is observed for complex 1 when it is measured at 10 K.

Three d(10)-d(10) transition-metal complexes with organosulfur ligands, Cu(6)(btt)(6) (1), Cu(4)(btt)(4) (2), and Ag(6)(bmt)(6) x 6 THF (3) (Hbtt = 2-benzothiazolethiol, Hbmt = 2-benzimidazolethiol, and THF = tetrahydrofuran), were synthesized and characterized. Complexes 1 and 2 with similar coordination environments are isomers crystallized from the same solvothermal reactions, but they cause great differences in both the structures and luminescent behaviors. The hexanuclear cluster 1 exhibits unusual near-infrared luminescence and high thermal stability, while complex 2 with tetranuclear cores and stronger metal-metal bonds shows an intense red emission like that from complex 3.

A new mixed-valence hexadecavanadate cluster compound, (Me2NH2)4[H6V16O42(SO4)] · 8H2O (1), has been synthesized via an efficient method in organic media. The hollow cluster shell of 1, with a sulfate ion locating in its centre, exhibits four large eight-membered –O–V–O–V– rings on its surface, which makes the cluster into a half-open structure distinguished from the common hollow clusters built up with closed surfaces. The intense blue luminescence of 1 in solution state is scarcely reported for the polyoxometalate clusters.

Reactions of VO2(acac) (Hacac = acetylacetone) and 2,6-Di(hydroxymethyl)-4-methylphenol (H3L) in different organic solvents give rise to two pseudopolymorphs of a new dinuclear oxovanadium(V) compound, [Et3NH]2[V2O4(HL)2] (1) and [Et3NH]2[V2O4(HL)2]·H2O (2). The compounds have been synthesized and characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. X-ray diffraction analyses reveal that 1 and 2 have different weak interactions and display remarkably distinct hydrogen-bonded networks.

Three lanthanide–organic frameworks formulated as [Yb2(1,3-pda)3(H2O)]n·nH2O (1) [La2(2,5-pydc)3(H2O)2]n (2) and [La(2,5-pydc)(2,5-Hpydc)(H2O)2]n·nH2O (3) (H21,3-pda=1,3-phenylenediacetic acid, H22,5-pydc=pyridine-2,5-dicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. Both the frameworks of compounds 1 and 2 exhibit intricate 3D architectures which can be simplified as nets with mixed nodes. Compound 1 presents a very complicated net with five types of nodes comprising intersecting (3,4)-connected and CdSO4 nets. Compound 2 possesses a (4,4,6)-connected net with (4284)(4462)2(4966)2 circuit symbol. While compound 3 is a 2D layer based upon carboxyl-bridged LaIII chains.

A dinuclear vanadium 24-membered macrocycle with double-ring, [V 2 O 2 L 2 (μ-CH 3 COO)] − (H 2 L = 3,3′-(1,3,4-thiadiazole-2,5-diyl)bis(sulfane-diyl) bis(4-hydroxypent-3-en-2-one)), was prepared in high yield from the reaction of VO 2 (acac) with 2,5-dimercapto-1,3,4-thiadiazole dipotassium salt (K 2 SSS) and acetylacetone (Hacac) at room temperature. Its closure of 24-membered macrocycle has resulted from the formation of U-shape units via S–C bonding between original SSS 2− and acac − ligands, while the bridging CH 3 COO − has created from an unexpected decomposition of Hacac. The obtained two products were characterized by single crystal X-ray diffraction, XRD, ESR, TGA and magnetism analyses. A possible mechanism for formation of the bimetal 24-membered macrocycle has been discussed.

Five new polyoxovanadate-based cluster compounds, (Et4N)4[HV15O39(acac)Cl]·3CH3CN (1), (Et4N)5[V16O40X] (X = Br 2a; X = Cl 2b), (Me2NH2)8[H2V16O42(ClO4)]·4H2O (3), and (Me2NH2)2(Et4N)2[H2V10O28] (4), having different types of vanadium oxide shells are isolated in organic media. Compounds 1−3 are hollow structures with different encapsulated anions in their centers. The surfaces of four compounds are constituted by vanadium and oxygen atoms, showing large 10-membered -O−V−O−V- rings and/or eight-membered -O−V−O−V- rings, which distinguish vanadium-oxide clusters from the common hollow clusters built up with closed surfaces.

Single crystals of [W11Ni1P1O39(Hbpy)](H2bpy)2 · 4.25H2O (1) and (W11Zn1P1O39)(H2bpy)2(Hbpy) · 1.5H2O (2) have been hydrothermally synthesized at 160 °C and both characterized by IR, elemental and single-crystal structural analyses. Compound 1 has a ladder-like chain structure by hydrogen bonding interactions, whereas 2 contains an unprecedented chain of Keggin polyoxotungstates by oxo-bridges and form a 2-D layer via hydrogen bonds.

An attractive carboxamido-containing ligand 2,2′-bipyridyl-3,3′-bis(N,N′-disalicylidene)-formyhydrazone (H4L), two binary cocrystals H4L·H2O and H4L·2CH3OH, and four bimetallic nanostructures, namely, molecule cleft [Cu2(L)(Im)2]·(CH3)2CO (1) and squares [Fe2(H2L)2](ClO4)·2H2O (2), [Fe2(H2L)2]·4H2O (3), and [Mn2(L)(H2L)]·4H2O (4) (Im = imidazole) were synthesized and characterized. H4L with plentiful chemical information, such as allosteric interaction, ketone and enol isomers, potential axial chirality and multiple binding sites, and valent states can be recognized in assemblies. In cocrystals H4L·H2O and H4L·2CH3OH, the conformations of H4L altered by solvent-assisted interactions in turn affect the hydrogen-bonding assembly of (R)-H4L and (S)-H4L molecules in solid. The architectures of bimetallic cleft 1 and squares 2−4 are mainly determined by the cooperation of the metal’s coordination modes and the conformations of H4L. Complexes 1−4 contain discrete chiral dimeric units, further extending to multi...

Five new d8 and d10 metal complexes, Pd(8-hq)2 (1), [Ag(8-Hhq)2]NO3 (2), Ag(8-hq)(8-Hhq) (3), [(8-H2hq)2PdCl4]·2H2O (4), and Pt(8-hq)(tht)Cl (5) (tht = tetrahydrothiophene), all with a fluorogenic chelating agent, 8-hydroxyquinaldine (8-Hhq), have been synthesized and characterized. The aggregations of their photoactive metal centers through π−π stacking and hydrogen bonding interactions construct the interesting frameworks. The strong emissions of 1−3 and 5 in solid states with orange, cyan, and green luminescences originating from metal···metal and π−π interactions are assigned as metal to ligand charge transfer/metal–metal to ligand charge transfer/intraligand emissions. The solvent effects on their photophysical properties are examined, which exhibit a wide range of strong luminescences in the different organic solvents. In addition, time-dependent density functional theory calculations using the B3LYP functional on 1 are in good agreement with the experiments. Thermogravimetric analyses and UV/vis sp...

Two coordination polymers, [In(btc)(2,2′-bpy)(H2O)]n · nH2O (1) and [In2(btec)(2,2′-bpy)2Cl2]n (2) (H3btc = 1,3,5-benzenetricarboxylic acid, H4btec = 1,2,4,5-benzenetetracarboxylic acid, 2,2′-bpy = 2,2′-bipyridine), have been prepared under hydrothermal conditions. Single-crystal X-ray diffraction analyses reveal that compounds 1 and 2 consist of two-dimensional double layer structures with (3, 3) grids and (4, 2) grids, respectively. The grids along two different directions in 1 are of the opposite chirality, while the interactions of double-layer sheets in 2 create a three-dimensional supramolecular network with one-dimensional tunnels. The additional green luminescences for both 1 and 2 in the solid state at low temperature imply the red shift of emission energy in the compounds, which may derive from LMCT. Their X-ray powder diffractions and thermogravimetric analyses are also discussed.

A novel one-dimensional (1D) coordination polymer built from tetracobalt(II)-p-sulfonatothiacalix[4]arene cluster units was prepared and characterized. Single crystal X-ray diffraction analyses reveal that each cavity of p-sulfonatothiacalix[4]arene in the polymer captures a hydrated cobalt(II) cation. The magnetic studies in the 2–300 K range show weak antiferromagnetic interactions between the four cobalt(II) centers.

Reactions of cobalt(II) nitrate or zinc(II) nitrate, tetrasodium p-sulfonatothiacalix[4]arene (Na4H4TCAS), and methylviologen dihexafluorophosphate (MV(PF6)2) afforded two isomorphous complexes, {[M(H2O)6]2 + [MV]2 + [(MV)2M2(H2O)4(H2TCAS)2]4 − }·14H2O (M = Co, 1; Zn, 2). In these two complexes, each two thiacalixarenes form a dimer with C i symmetry through the coordination of sulfonate groups, and the above dimers further extend their structures through second-sphere coordination and π…π stacking interactions into three-dimension nets.

Pyridine-2,6-dicarboxylic acid (H2PDA) reacted with Dy2O3 under hydrothermal conditions to form a novel lanthanide–organic framework [Dy2(PDA)3(H2O)4]n·6nH2O (1). Compounds 1 crystallizes in monoclinic system, space group P21/c. In 1, a square motif as a building block constructed by four Dy3+ ions was further assembled into a highly ordered 2D (4,4) grid. While the self-assembly of H2PDA and Sm2O3 under hydrothermal conditions produced [Sm2(PDA)3(H2O)6]n·2nH2O (2). Compound 2 crystallizes in triclinic system, space group P-1, and shows a 1D coordination polymeric chain built from dimeric units of Sm3+ ions. Furthermore, the luminescent properties of both 1 and 2 were studied.

By use of the three-layer diffusion method, reactions of flexible bipyridyl ligands (4,4'-bpp or 3,3'-bpp) with M(II) salts (M = Zn, Cd) and multi-carboxylate ligands resulted in the formation of four interesting d(10) metal-organic coordination polymers: [Zn(mu-4,4'-bpp)Br-2](n) (1), [Zn(mu-4,4'-bpp)(l,2-bdc)](n) center dot nH(2)O (2), [Zn(mu-3,3'-bpp)(1,3-bdc)](n) center dot nCH(3)OH center dot 2nH(2)O (3) and [Cd(mu-3,3'-bpp)(C4H2O4)](n) center dot 3nH(2)O (4) (4,4'-bpp = 2,2'-bis(4-pyridylmethyleneoxy)- 1,1'-biphenylene; 3,3'-bpp = 2,2 '-bis(3-pyridylmethyleneoxy)-1,1'-biphenylene; bdc=benzenedicarboxylate, C4H4O4 = fumaric acid). Complex 1 has a 2D sheet structure consisting of two unusual zigzag Zn(II) chains which are nearly perpendicular to each other. Complex 2 is comprised of two-leg ladders, in which [Zn(4,4'-bpp)] chains serve as the side rails and 1,2-bdc ligands serve as the cross rungs. In complex 3, every two 1,3-bdc ligands connect the neighbouring Zn(II)-3,3'-bpp dimetallic rings in eta(1) coordination modes into an interesting chain structure. Complex 4 consists of an anionic macrocycle-containing cadmium dicarboxylate sheets that are separated by 3,3'-bpp. These d(10) metal complexes exhibit high thermal stabilities and strong luminescence efficiencies. (c) 2007 Elsevier Ltd. All rights reserved.

A novel layered inorganic-organic hybrid polymer, [Cd-3(mu(3)-OH)(2)(mu(2)-Cl)(2)L-2(H2O)(2)] (HL = 4-aminocinnamic acid), with strong blue luminescence has been reported. Its particular arrangement of the Cd(II), Cl-, and OH- forming an infinite one-dimensional inorganic connectivity with the chair-like Cd4Cl2(OH)(2) features is a new example of mixed Cd-OH-Cl discrete compounds. (c) 2007 Elsevier B.V. All rights reserved.

The reaction of tetrasodium p-sulfonatothiacalix[4]arene (Na4H4TCAS), copper(II) nitrate and pyridine N-oxide (PNO) afforded a yellow copper(II)-p-sulfonatothiacalix[4]arene complex. X-ray diffraction analysis displays that it is an interesting dimeric supramolecular capsule, [Cu2(PNO)2(H2O)6]4+ ⊂ [(H6TCAS)2]4 − ·22H2O, in which two PNO molecules bridge the two CuII ions in the O,O′-μ2 mode and the hydrophobic aromatic rings point into the cavities of the thiacalixarenes. Interestingly, the thiacalixarenes pack themselves into the closed pores through π…π interactions in ab plane, and these pores further link to each other through hydrogen bonding to construct infinite hydrophilic tunnels, which fill with the disordered water molecules as the guests. In a dimeric supramolecular capsule, [Cu2(PNO)2 (H2O)6]4+ ⊂ [(H6TCAS)2]4·22H2O, two PNO molecules bridge the two CuII ions in the O,O′-μ2 mode and the hydrophobic aromatic rings point into the cavities of the thiacalixarenes. Interestingly, the thiacalixarene...

A porous anionic framework with cubic symmetry and multi-intersecting open channels, {[H2tmdp]3[In6(btc)8]·40H2O}n (1) (tmdp= 4,4‘-trimethylene dipiperidine, H3btc=1,3,5-benzenetricarboxylic acid), is reported. Complex 1 crystallizes in the cubic space group I43d (a = b = c = 20.3732(8) A, V = 8456.2(6) A3, and Z = 2). Its cagelike units, In9(btc)11, constitute a large accessible void with 65.4% of the total volume. The cationic guests located in the channels can be exchanged with inorganic ions, such as K+, NH4+, Ca2+, Sr2+, and Ba2+.

Reactions of p-sulfonatothiacalix [4]arene (Na4H4TCAS), Cu(NO3)2·3H2O, and 2,2‘-bipyridine (2,2‘-bpy) with/without silver(I) ions generated a self-complementary homometallic anionic dimer [Cu(2,2‘-bpy)3][Cu3(HTCAS)(2,2‘-bpy)4]2·14H2O·CH3OH (1) and a heterometallic cluster {Ag3Cu5[H3(TCAS)2](2,2‘-bpy)8(H2O)}·31H2O (2). In these two complexes the cone-like conformation of p-sulfonatothiacalix [4]arene is fixed by the metal centers through coordination with the phenolic groups and thioether bridges at the lower rim of p-sulfonatothiacalix [4]arene. Interestingly, these two complexes display completely different structural motifs: head-to-head supramolecular dimers and tail-to-tail ditopic cups, while both 1 and 2 show several different types of capture of Cu-2,2‘-bpy complexes. A variable-temperature magnetic susceptibility study of 1 indicates that there are weak ferromagnetic interactions between Cu(II) ions through the phenolic group bridge and very weak intermolecular antiferromagnetic interactions.

Two new 2D coordination polymers, [Ag4(μ-4,4′-bpp)3(1,3-bdc)2]n · 2nH2O (1) and [Ag(μ-4,4′-bpp)2ClO4]n(2) (4,4′-bpp = 2,2′-bis(4-pyridylmethyleneoxy)-1,1′-biphenylene; 1,3-bdc = 1,3-benzenedicarboxylate) have been synthesized using three-layer diffusion methods. Single-crystal X-ray analyses reveal that they are both extended grid networks of the (4,4) topology. In complex 1, a chain built by Ag(I) centers with T-shaped and linear geometries is further connected by the interesting ligand-unsupported Ag⋯Ag interactions as well as the conjugated π systems to form an interdigitated 2-D coordination network. The corrugated (4,4) sheets of 2 are packed in the ab planes and stacked along the c direction with the anions ClO 4 - occupying the gaps in the squares.

Two new complexes [Ni(pydc)(H2O)2]n (1) and [Ni2(pydc)2(H2O)5]n (2) (H2pydc = 2,4-pyridinedicarboxylic acid) have been obtained by hydrothermal synthetic method and characterized by single crystal X-ray analysis. In 1 six-coordinate Ni(II) ions are coordinated by pydc ligands to form 2-D layer structures; while in 2 six-coordinate Ni(II) ions are only connected into 1-D zigzag chains constructed by dinuclear nickel units. Although the coordination geometries around Ni(II) centers in both complexes are similar, their structure topologies are greatly tuned by coordination modes of pydc. Variable temperature magnetic susceptibility studies have shown that both compounds 1 and 2 may display antiferromagnetic coupling between paramagnetic metal centers mediated by bridging carboxylate groups.

A series of new lanthanide hybrids [Ln3(mu-OH)4 (2,5-pydc)(2,5-Hpydc)3(H2O)4]n (Ln = Gd (1), Dy (2), Er (3), Eu (4), Sm (5), Yb (6), Y (7); 2,5-pydc=pyridine-2,5-dicarboxylate), as clustered lanthanide oxide ring tunnels with helical dodecahedral chains and fully 3D Ln-O-Ln connectivity, has been hydrothermally synthesized and characterized. The inorganic skeleton of the hybrid can be specified by the Schläfli symbol (6210)2 (64102) as a single 3D (3,4)-connected net. The luminescence properties have been studied, and the results showed that the Dy(III) (2) and Eu(III) (4) complexes exhibited sensitized luminescence in the visible region. Variable-temperature magnetic susceptibility measurements of 1-6 showed that the complexes 1-3 are nearly paramagnets, whereas the depopulation of the Stark levels in complexes 4-6 leads to a continuous decrease in mu(eff) when the sample is cooled from 300 to 2 K.

Six tetranuclear cadmium(II) complexes, Na[Cd4(hmt)2(H2O)6(dpa)4(NO3)]·8H2O (1), Na[Cd4(hmt)2(CH3OH)2(H2O)4(dpa)4I]·8H2O (2), Na[Cd4(hmt)2(H2O)6(dpa)4Br]·8H2O (3), Na2[Cd4(hmt)2(H2O)6(dpa)4(SCN)2]·4H2O (4), {Na[Cd4(hmt)2(H2O)6(dpa)4Cl](H2O)4}n (5), and {[Cd4(hmt)3(H2O)5(dpa)4](H2O)10}n (6) (hmt = hexamethylenetetramine, H2dpa = diphenic acid), were synthesized by reactions of H2dpa, hmt, and CdX2 (X = NO3-, I-, Br-, Cl-, SCN-, and OAc-). All the complexes contain a basic unit [Cd4(dpa)4], in which four dpa ligands in a chelating bis-bidentate coordination mode link two six-coordinate and two seven-coordinate cadmium(II) centers. The research result demonstrates that the nature of the counterions has an important effect on the assembly process of neutral and anionic mixed ligands with metal ions. In 1−3, NO3-, I-, or Br- bridges the two seven-coordinate CdII centers of the unit to form a discrete tetranuclear molecule with a cis-conformation and hmt as a terminal ligand coordinated to each of the two six-c...

Three novel coordination polymers, [Cu2(adip)(H2O)4]n·nH2O (1), [Co3(Hadip)2(H2O)6]n·2nH2O (2), and [Zn7(adip)4(H2O)10K2(H2O)2]n·4nH2O (3), were solvothermally synthesized by adopting a new type of multicarboxylate ligand, H4adip (H4adip = 5-aminodiacetic isophthalic acid). Compound 1 features a 1D tube-like structure, compound 2 shows novel 2D (3,4)-connected nets, and compound 3 possesses an interesting 3D architecture, all of which possess channels hosting guest water molecules. A particular interest of the adip4- ligand is its propensity to bind metal ions forming various metallocycles, which could be viewed as the basic building blocks in the construction of supramolecular frameworks. Thermogravimetric analyses (TGA) were performed on compounds 1, 2, and 3. Variable-temperature magnetic susceptibility of 2 was investigated. An intense blue luminescence with an emission band peaking at 454 nm observed for 3 may result from ligand-to-metal charge transfer (LMCT).

Assembly of InCl3 with 1,3,5-benzenetricarboxylic acid (H3btc) and pyridine or pyridine derivatives under hydrothermal conditions produces a series of isostructural coordination polymers with the interesting frameworks: {(HL)[In4(OH)4(btc)3]·L·3H2O}n, L=pyridine (1); L=2-picoline (2); L=4-picoline (3) and {(Hdpea)[In4(OH)4(btc)3]·3H2O}n (4) (dpea=1,2-di(4-pyridyl)ethane). In these four complexes, carboxyl and hydroxyl oxygen atoms bridge indium(III) centers to form octahedral chain-like sinusoidal curves, which are further interlinked by btc3− moieties to generate 3-D frameworks with 1-D channels. The protonated guests HL in 1–3 located at the channels can be fully exchanged by K+ ion or partially exchanged by Sr2+, and Ba2+ ions.

The self-assembly of d,l-amino acids and Cu(NO3)2·3H2O with 4,4‘-bipyridine in basic ethanol/aqueous solution gave rise to two distinct three-dimensional (3D) supramolecular architectures {[Cu2(d-ala)(l-ala)(4,4‘-bipy)2](NO3)2·5H2O}n (1) and {[Cu2(d-phe)(l-phe)(4,4‘-bipy)2](NO3)(OH)·5H2O}n (ala = alanine anion, phe = phenylalanine anion, 4,4‘-bipy = 4,4‘-bipyridine) (2). In 1, Cu(II) centers chelated by deprotoned d,l-alanine direct linear 4,4‘-bipy to form a one-dimensional (1D) helical chain, which is further assembled into 3D helical array through interchain hydrogen bonds and anion guest chains. In 2, Cu(II) centers chelated by deprotoned d,l-phenylalanine direct 4,4‘-bipy to form a 1D twisted coordination polymeric chain that interacts with four adjacent chains through complementary coordination interactions and two chains through weak π−π interactions to give a 3D porous framework.

Two new compact molecular capsules of p-sulfonatothiacalix[4]arene with sodium ions have been synthesized by inducing suitable guest molecules, 1,2-bis(imidazol-1‘-yl)ethane or 2,2‘-bipyridine. Single-crystal X-ray diffraction analyses reveal that these supramolecular compounds possess open or close capsule conformations in a zigzag-like chain or a straight-line chain array. 1H NMR spectroscopic studies confirm that the above stable molecular capsules are present in solution. Their guest molecules in both compounds are well accommodated by p-sulfonatothiacalix[4]arene capsules via a variety of supramolecular interactions.

A series of new copper(II) complexes with pyridine–carboxylate ligands: [Cu2(μ-Cl)2(pda)2][Cu(MeOH)(H2O)4]·H2O (1), [CuBr(pda)(MeOH)]2[Cu(H2O)5]·MeOH (2), [Cu2(μ-Br)2(pda)2][Cu(H2O)4]·[CuBr2(H2O)2] (3) and [CuNa2(μ-sna)2]·4H2O (4) (H2pda=pyridine-2,6-dicarboxylic acid, H2sna=2-sulfinonicotinic acid), have been synthesized and structurally characterized. The weak non-covalent interactions of π–π stacking and hydrogen bonding between the pyridine–carboxylate ligands extend complexes 1–4 into supramolecular architectures, where complexes 1 and 3 possess 2D networks with wave-like chains or straight chains, while complexes 2 and 4 show 2D layers and 3D networks with infinite 1D channels, respectively. The polycrystalline powder EPR spectra of complexes 1, 3 and 4 indicate that their unpaired electrons are placed in d x 2 − y 2 or d z 2 orbitals of the ground state of Cu(II). The UV/vis, IR spectra and TG analyses for complexes 1–4 are also discussed.

Two novel metal-organic coordination polymers, [Mn2(dpa)2(4,4′-bipy)2(H2O)2]n (1) and [Mn(Hdpa)2(bpe)(H2O)2]n (2) (H2dpa = diphenic acid, 4,4′-bipy = 4,4′-dipyridine, bpe = 1,2-bis(4-pyridyl)ethene), have been hydrothermally synthesized. Single crystal X-ray diffraction analyses reveal the two-dimensional and three-dimensional structures for complexes 1 and 2, respectively. In 1, the dpa ligands link metal ions with different modes into one-dimensional chains, and the 4,4′-bipy terminally coordinate to the metal ions extending the chains into a layer. Whereas in 2, the flexible bpe ligands link the structure motifs into chains, and the hydrogen bonding interactions between the chains lead to the formation of cavity structure.

Hydrothermal reactions of InCl3 with pyromellitic dianhydride and pyridine derivatives produce three coordination polymers: {(HL)[In3(btec)2(OH)2]·L}n [btec = 1,2,4,5-benzenetetracarboxylate, L = 2-picoline (1), L = 4-picoline (2)] and {(Hdpea)[In3(btec)2(OH)2]}n [dpea = 1,2-bis(4-pyridyl)ethane] (3). Single crystal X-ray diffraction and powder X-ray diffraction analyses reveal that compounds 1–3 are isostructural and possess the same 3D framework as 1D open channels. Thermal gravimetric studies show that compounds 1–3 are stable up to 300 °C. The guests of the protonated pyridine derivatives located at the channels in 1 and 2 can be fully exchanged by Ca2+ and Ba2+ ions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The reactions of 4-aminobenzoic acid (4-abaH), 4,4′-bipyridine (4,4′-bipy) and transitional metal ions (ZnII, MnII and CuII) gave rise to four supramolecular architectures, namely, [(4-abaH)2(4,4′-bipy)] (1), {[Zn2(4,4′-bipy)2(4-aba)4] (H2O)5}n (2), {[Mn(4,4′-bipy)2(H2O)4] (4-aba)Br(H2O)3} (3) and {[Cu2(4,4′-bipy)3(H2O)2(4-aba)2](NO3)2(H2O)4}n (4). Their crystal structures were determined by X-ray diffraction and show different structural motifs. 1 is a one-dimensional hydrogen bonding ladder constructed by 4-abaH and 4,4′-bipy. In 2, 4,4′-bipy bridges Zn(4-aba)2 units forming a one-dimensional zigzag chain, which is extended into a three-dimensional framework by crystalline water molecules through hydrogen bonding interactions. Three-dimensional network of 3 is constructed by mononuclear [Mn(4,4′-bipy)2(H2O)4]2+ cations, neutral crystalline water molecules, and 4-aba and Br− anions through extensive hydrogen bonding and π–π interactions. However, one-dimensional ladder formed by 4,4′-bipy and Cu(4-aba) units in 4 is extended into a three-dimensional architecture through interpenetration of the lateral 4-aba arms into squares of the adjacent Cu–(4,4′-bipy) ladders and extensive hydrogen bonding interactions.

A novel 2D bilayer framework [Cd3(nta)4(dca)2(H2O)4]n (1) (Hnta=nicotinic acid, Hdca=dicyanoamide) was obtained by slowly diffusion of a CdCl2 aqueous solution into a mixture of sodium dicyanoamide, Hnta and NaOH aqueous solution in a U-tube. The framework of 1 consists of a molecular ladder containing [Cd6(nta)6] rectangular metallomacrocyles, and the ladders are further linked by end-to-end dicyanoamide bridges to form a unique 2D bilayer framework. Supramolecular organization of π⋯π interaction between adjacent layers extends the 2D bilayer into a 3D network. Complex 1 is stable up to 315 °C and exhibits a strong fluorescent emission band at 580 nm (λex=314 nm) in the solid state.