Search

A quaternary metal chalcogenide, namely K2CdGe3S8 (I), is obtained through a high-temperature solid-state approach. Compound I crystallizes with the non-centrosymmetric space group P212121. It features a 2D layer structure with [CdGe3S8] layers consisting of tetrahedral GeS4 and CdS4 units, and counter K+ embedded between the layers. The compound exhibits a powder second-harmonic generation (SHG) response of ~0.1 times that of KH2PO4 (KDP) with phase-matchable character at the laser wavelength of 1064 nm. Remarkably, it has a wide band gap (3.20 eV), which corresponds to a favorable high laser-induced damage threshold of 6.7 times that of AgGaS2. In addition, the calculated birefringence (Δn) is 0.039 at the wavelength of 1064 nm, which satisfies the Δn criteria for a promising infrared NLO material. [ABSTRACT FROM AUTHOR]

Superlattice materials offer new opportunities to modify optical and electrical properties of recently emerging 2D materials. The insertion of tetraethylbenzidine (EtDAB) into interlamination of the established 2D PbI2 semiconductor through a mild solution method yielded the first lead iodide superlattice, EtDAB⋅4PbI2 (EtDAB=tetraethylbenzidine), with radical and non‐radical forms. The non‐radical form has a non‐ionic structure that differs from the common ionic structures for inorganic–organic hybrid lead halides. The radical form shows five orders of magnitude greater conductance and broader photoconductive response range (UV/Vis → UV/Vis‐IR), than pure PbI2 and the non‐radical form of the superlattice. Lead the way: The first lead‐iodide superlattice constructed from non‐ionic organic molecules and PbI2 through van der Waals interactions is a new type of inorganic–organic hybrid and has a radical and a non‐radical form. The radical form has an almost five orders of magnitude greater conductivity and broader band photoconductive response than that of the non‐radical form or pure PbI2. [ABSTRACT FROM AUTHOR]

Solid-state X-ray scintillators are widely applied in medical imaging and space exploration. However, it is still a great challenge to probe into the intrinsic nature of scintillating behaviour due to the ambiguous structure–function relationship. Herein, four structure-defined X-ray scintillating Pb(ii)-based metal–organic frameworks (SMOFs) were successfully obtained under solvothermal conditions, [Pb(1,4-ndc)(DMF)]n (SMOF-1), [Pb(1,4-ndc)(DMA)]n (SMOF-2), [Pb2(2,6-ndc)2(H2O)]n·nDMF (SMOF-3) and [Pb4(2,6-ndc)3Cl2]n (SMOF-4), where 1,4-H2ndc = 1,4-naphthalene dicarboxylate, 2,6-H2ndc = 2,6-naphthalene dicarboxylate, DMF = N,N-dimethylformamide, and DMA = N,N-dimethylacetamide. SMOFs 1–4 show scintillating signals under X-rays triggered by a highly purified tungsten target. Compared with SMOFs 1–3, SMOF-4 exhibits excellent scintillating performance owing to its solvent-free and denser structure, which favours more efficient conversion ability of X-rays to visible light. X-ray stimulated luminescence (XSL) spectra present multiple emission peaks, which is further confirmed by wavelength-dependent luminescence spectra under UV-Vis light, and density of state and DFT calculations. The synergistic effects of heavy metal Pb(ii) centres as effective X-ray absorbers and organic ligands as luminescent motifs endow these Pb(ii)-based MOFs with application prospects in X-ray detection. [ABSTRACT FROM AUTHOR]

Abstract: We evaluated the individual atom contributions to the second harmonic generation (SHG) coefficients of LiCs2PO4 (LCPO) by introducing the partial response functionals on the basis of first principles calculations. The SHG response of LCPO is dominated by the metal‐cation‐centered groups CsO6 and LiO4, not by the nonmetal‐cation‐centered groups PO4 expected from the existing models and theories. The SHG coefficients of LCPO are determined mainly by the occupied orbitals O 2p and Cs 5p as well as by the unoccupied orbitals Cs 5d and Li 2p. For the SHG response of a material, the polarizable atomic orbitals of the occupied and the unoccupied states are both important. [ABSTRACT FROM AUTHOR]

We report the exploration of the stabilization effect of the in situ generated N-alkylated DABCO (DABCO = 1,4-diazabicyclo[2.2.2]octane) cation in the family of bromoplumbates and a 1-D bromoplumbate, (Et2DABCO)2n(Pb3Br10)n (1), has been prepared by solvothermal conditions. Optical diffuse reflectance determination shows the band gap of 1 is 3.69 eV, which manifests that 1 is a wide band gap semiconductor. Compared with the band gap of bulk PbBr2 (3.84 eV), 1 exhibits 0.15 eV red shift of absorption edge. While for the reported iodo analogs of this compound, (MPDA)2n(Pb3I10)n and (Et2DABCO)2n(Pb3I10)n, they exhibit 0.53 and 0.47 eV blue shift of the energy gaps compared with the measured value of 2.30 eV for bulk PbI2, respectively. The photoluminescent study of 1 shows that it exhibits a broad emission band centered at 697 nm upon photoexcitation by 345 nm (amount to 3.59 eV). The calculated density of states manifests the theoretical value of the band gap of 1 is 3.422 eV and the origination of photoluminescence can be ascribed to the transition of bonding electrons of Br– anion to the empty orbits of Pb(II) ion. [ABSTRACT FROM AUTHOR]

A novel pentanary selenide (K3I)[InB12(InSe4)3] was obtained via a high-temperature solid-state method. It crystallizes in the hexagonal space group P6322 which features an InSe4 tetrahedron consolidated B12 icosahedron and 1-D chain constructed by InSe6 octahedron and B12Se12 cluster alternatively connected along the c-axis. Second-order nonlinear optical property measurement shows that it is second harmonic generation-active. Theory calculation indicates that it is an indirect semiconductor with the energy gap of 1.15 eV. [ABSTRACT FROM AUTHOR]

We investigate the impact of different derivatives of 1,4-diazabicyclo[2.2.2]octane on the crystal structures of iodoplumbates by systematically increasing the size of the same organic amine, and present two new 1-D iodoplumbates. Optical studies reveal the semiconductor characteristics of all as-synthesized iodoplumbate hybrids. [ABSTRACT FROM AUTHOR]

Four Zn(ii) tetrazolate coordination compounds have been hydrothermally synthesized and structurally determined by single-crystal X-ray diffraction. They are formulated as [Zn(3-tzbd)2]n·nH2O (1), [Zn2(3-tzbd)2(OH)2(4,4′-bipy)]n·nH2O (2), [Zn2(3-tzbd)3(N3)(4,4′-bipy)2]n·nH2O (3) and Zn2(3-tzbd)4(phen)2 (4), where 3-Htzbd = 3-(5H-tetrazol)benzaldehyde. The 3-tzbd− ligand, which was in situ generated through a [2 + 3] cycloaddition reaction of nitrile and azide, displays diverse coordination modes. Compound 1 exhibits a (4,4)-connected two-dimensional (2D) layer generated by the linkage of dinuclear units of [Zn2(μ2-3-tzbd)2] and μ2-3-tzbd− ligands. In 2, Zn(ii) atoms are connected by μ2-3-tzbd− ligands and μ3-OH− anions to form unusual double-stranded stair-like chains, which are further linked by 4,4′-bipy to create a 2D sheet. Compound 3 features an unprecedented one-dimensional (1D) four-legged, triple-ladder chain composed of tetranuclear units [Zn4(μ2-3-tzbd)4(μ2-N3)2]. Two Zn(ii) atoms in 4 are bridged by μ2-3-tzbd− ligands to result in an isolated dinuclear structure. In addition, the luminescent properties of 1–4 were investigated in the solid state at room temperature. The relevant density of states (DOS) calculation results show that their photoluminescence mainly originates from ligand-centered emission and is dependent on the organic ligand incorporated into the compounds. [ABSTRACT FROM AUTHOR]

Abstract: Four triazole-bridging coordination complexes, [Zn4(ptr)2(SO4)3(μ 3-OH)2(H2O)4] n (1), [Hg(CN)2(ptr)] n (2), [Hg(Cl)2(ptr)] n (3), and [Cu2(μ 2-ptr)2(μ 2-F)2] n (SiF6) n ·2nH2O (4), were synthesized with (m-phenol)-1,2,4-triazole (ptr). Compounds 1–4 with extended structures of 4-substituted 1,2,4-triazole are rarely reported. The layered structure of 1 can be regarded as constructed from the 2-D inorganic backbone of SO4 2−(2) anions bridging [Zn4(μ 3-OH)2(H2O)2]6− subunits with the ptr ligands anchoring to both sides of backbone. Compounds 2 and 3 are the first mercury(II) complexes with 4-substituted 1,2,4-triazole, which feature the ptr ligand acting as a bidentate ligand bridging the Hg(II) atoms to form arciform –Hg–ptr–Hg–ptr chains. The structure of 4 is constructed from the F atoms bridging Cu atoms in symmetrical μ 2-coordination mode to form a zigzag cationic chain with each ptr ligand bridging a pair of Cu atom on the both sides, resulting in a nonplanar 5-membered [Cu2N2F] ring. Fluorescent properties of 1–4 were characterized and the magnetic property of 4 shows antiferromagnetic interaction between the copper(II) ions. [Copyright &y& Elsevier]

Two new Schiff-base compounds, 1,6-bis(4-dimethylaminobenzyl)-2,5-diaza-1,5-hexadiene (bdh), 1,4-bis(4-dimethylaminobenzyl)-2,3-diaza-1,3-butadiene (bdb), and a silver complex of the latter ([Ag 2 (bdb) 3 (NO 3 ) 2 ]·H 2 O, 1) have been synthesized and characterized. The crystal structure of complex 1 was determined. 1 is a dinuclear complex, with the silver ions lying in coordination tetrahedra formed by two nitrogen atoms from the bdb ligands and two oxygen atoms from the nitrate anions. The fluorescence properties of bdh and bdb were studied; the fluorescence of bdb was quenched by the addition of silver ions, indicating that it is a potential fluorescent reagent for the analysis of silver. [ABSTRACT FROM AUTHOR]

The exploration and development of second-order nonlinear optical (NLO) materials in the middle- and far infrared (MFIR) region are important and high profile topics in the fields of NLO, solid-state chemistry and laser. Common MFIR NLO materials are chalcogenides, halides, and iodates, which have a wide MFIR transparent range and large NLO coefficients. This review summarizes recent achievements on MFIR NLO materials, and specifically focuses on their crystal structures and NLO properties. Compared to known materials, the common choice for cations are alkali-metal Li, Na, K, Rb and Cs, the coin-metal Ag, and the alkali-earth metal Ba. Exploring mixed-anions materials could be one of the most promising solutions to obtaining NLO materials with both large second-harmonic generation (SHG) intensities and high laser induced damage thresholds (LIDTs). This review also summarizes functional moiety theory to elucidate the design of promising NLO materials. [ABSTRACT FROM AUTHOR]

Three new ternary rare-earth zirconium chalcogenides, Ce 2 ZrSe 5 ( 1 ), Pr 2 ZrSe 5 ( 2 ) and Nd 2 ZrSe 5 ( 3 ), have been synthesized by a facile solid-state route with boron as the reducing reagent. They crystallize in the space group Pnma of the orthorhombic system, belonging to the U 3 Se 5 structure type. Their 3-D structures are constructed by parallel polyanionic {[ZrSe 5 ] 6– } n chains and LnSe 8 bicapped trigonal prisms. The magnetic susceptibilities' data indicate their antiferromagnetic-like behavior without magnetic order down to 2 K. The structural relationships among several similar structures are discussed, together with the lanthanide contraction in the Ln 2 ZrSe 5 system. [ABSTRACT FROM AUTHOR]

Five coordination polymers 1–5with four types of (4,4) layers havebeen synthesized through anew strategy of designing their crystal structures based on (4,4)topology. Compound [Co(adc)(bpp)(H2O)]n(1) presents a 2-D structurewith 2-fold homointerpenetration of layer A, while the2-D compound {[Ni(adc)(bpp)2(H2O)]2·bpp}n(2) presents 2-fold heterointerpenetration of layer Bandlayer C. Compound [Zn(adc)(bpp)·DMF]n(3) displays a typical 2-D→ 3-D parallel interpenetrating structure of layer D. Compounds [Ni(Cladc)(bpp)(H2O)]n(4) and [Co(Cladc)(bpp)(H2O)]n(5) are isomorphousand display similar structures to 1. (H2adc= 4,4′-azodibenzoic acid, ClH2adc = 3,3′-dichloro-4,4′-azodibenzoicacid, bpp = 1,3-di(4-pyridyl)propane, DMF = N,N-dimethylformamide). Luminescence propertiesand thermal stabilities of 1–5havebeen explored. [ABSTRACT FROM AUTHOR]

Abstract: In our investigation of non-centrosymmetric rare earth sulfides in the La3AgSnS7/KBr, LaAlGeS5/NaBr, HoAlGeS5/KBr, ErAlGeS5/NaBr, Er3AgGeS7/KBr and La3NaSnS7/NaBr systems, five compounds belonging to the R6B2C2Q14 family have been obtained. These compounds crystallize in the P63 space group, and the crystal data are as follows—La3AgSnS7: a =10.3780(15)Å, c =5.9900(12)Å, Z =2; La3Ge0.25GeS7: a =10.2970(15)Å, c =5.8120(12)Å, Z =2; Ho3Ge0.272(10)GeS7: a =9.6480(14)Å, c =5.7920(12)Å, Z =2; Er3Ge0.330(10)GeS7: a =9.5930(14)Å, c =5.8490(12)Å, Z =2; La3Sn0.25SnS7: a =10.2770(15)Å, c =6.0030(12)Å, Z =2. Single-crystal analysis indicated that the crystal structures consist of three types of building block: LnS n , MS4, and AgS3 (for La3AgSnS7) or MS6 units (for Ln3M x MS7, Ln=La, Ho, Er; M=Ge, Sn; 1/4≤ x ≤1/2), as any other compounds belonging to the R6B2C2Q14 family. Ln3M x MS7 (Ln=La, Ho, Er; M=Ge, Sn; 1/4≤ x ≤1/2) are deficient compounds with the B sites occupied partly by M(II), and/or M(IV). [Copyright &y& Elsevier]

Abstract: Four homotrinuclear linear coordination compounds with bridging ligand of (m-phenol)-1,2,4-triazole, [Mn3(L)6(H2O)6](ClO4)6 (1), [Ni3(L)6(H2O)6](BF4)6·4DMF (2), [Cd3(L)6(H2O)6](ClO4)6· 2H2O·2DMF·2EtOH (3), [Zn3(L)8(H2O)4](BF4)4(SiF6)·2EtOH·12H2O (4), have been synthesized and structurally determined. The structures consist of three metal ions in linear arrangements, linked to each other by two pairs of three N1, N2 bridging triazole ligands. The negative value of J suggests that antiferromagnetic interaction exists in 1. Green fluorescence of 2 and 4 with emissions at 518nm for 2 and 524 for 4 is possibly assigned to LMCT. The energy gaps of the compounds 2 and 4 are 1.82 and 1.97eV, respectively, which suggests that the two materials behave as semiconductors. [Copyright &y& Elsevier]

Abstract: The reactions of two kinds of substituted 1,2,4-triazoles with BiI3 yielded three inorganic–organic hybrids: [HL1]4[Bi6I22]·[L1]4·4H2O (1) (L1=3-(1,2,4-triazole-4-yl)-1H-1,2,4-triazole); [HL2]4[Bi6I22]·6H2O (2); [HL2]2[Bi2I8]·[L2]2 (3) (L2=(m-phenol)-1,2,4-triazole). Both 1 and 2 have polynuclear anions of [Bi6I22]4– to build up the inorganic layers and substituted 1,2,4-triazoles as the organic layers. Hybrid 3 consists of two BiI5 square pyramids as inorganic layers. There exist hydrogen bondings and I⋯I interactions in the structures of 1, 2 and 3. Optical absorption spectra of 1, 2 and 3 reveal the presence of sharp optical gaps of 1.77, 1.77 and 2.07eV, respectively, suggesting that these materials behave as semiconductors. [Copyright &y& Elsevier]

Abstract: A six-coordinated monomeric CoII complex, [Co(L)2(H2O)4]·10H2O (1), where HL=4-(p-benzoxy)-1,2,4-triazole, has been synthesized and characterized by elemental analyses, IR, thermogravimetric analysis and X-ray diffraction technique. Structural analyses reveal that the CoII center has a CoN2O4 octahedral environment with four O atoms of coordinated water molecules constituting the equatorial plane and two N atoms of two distinct L ligands occupying the two axial sites in 1. A striking structural feature of 1 resides in the formation of a three-dimensional (3D) supramolecular architecture through intermolecular O–H⋯O hydrogen-bonding interactions. Complex 1 displays strong blue emission in the solid state. [Copyright &y& Elsevier]

Abstract: Reaction of the 2-D MOF [AgL] n ·nH2O (1; L=4-cyanobenzoate) with pyrazine (L′) in water yielded [Ag2L2L′] n ·2nH2O (2) with a chain-like structure. Compound 1 features tunable yellow-to-white photoluminescence when its wavelength of excitation light varies. The photoluminescence of 2 obviously differs from that of 1: the former displays intense yellowish green phosphorescence with a shorter lifetime of ~3.58μs and an unresolved peak shape, and does not exhibit tunable photoluminescence upon irradiation of 280–380nm UV light. Electron transition from the [Ag2(COO)2] cluster to pyrazine is probably responsible for the phosphorescence of 2 based on the experimental and theoretical results. [Copyright &y& Elsevier]

Crystals with mixed anions refer to inorganic salts containing at least two types of anions or anionic groups, and these anions can be Q 2− (Q = O, S, Se, Te) and X − (X = F, Cl, Br, I), and anionic groups include various B–O groups, (OH) − , (IO 3 ) − , (CO 3 ) 2− , (SiO 4 ) 4− , (NO 3 ) 3− and (PO 4 ) 3− . Recently, in view of the insufficiency and strong requirements of second-order nonlinear optical (NLO) crystals, especially ones in the deep ultraviolet (DUV) and middle and far-infrared (MFIR) regions, the study of NLO crystals have received intensive interest from researchers. For a NLO crystal candidate, desirable properties include large NLO coefficients, high laser-induced damage threshold values, phase matchabilities and wide transparent windows. The availability of the former two properties is especially problematic since the structural factor influences them in reverse order. To balance them, it is necessary to introduce different anions into the structure to induce them to function differently. Under the guidance of anionic group theory and the functional moiety concept, many NLO crystals with mixed anions have been obtained. However, to date, a systematic survey of this topic has not been carried out. In this review, recently reported NLO crystals with mixed anions are summarized, the contents of which are mainly focused on their crystal structures and NLO behaviors, together with the relationship between these two aspects. It is hoped that this work will provide a useful perspective on the most promising NLO candidates. [ABSTRACT FROM AUTHOR]

A novel pentanary selenide (K3I)[InB12(InSe4)3] was obtained via a high-temperature solid-state method. It crystallizes in the hexagonal space group P6322 which features an InSe4 tetrahedron consolidated B12 icosahedron and 1-D chain constructed by InSe6 octahedron and B12Se12 cluster alternatively connected along the c-axis. Second-order nonlinear optical property measurement shows that it is second harmonic generation-active. Theory calculation indicates that it is an indirect semiconductor with the energy gap of 1.15 eV. [ABSTRACT FROM AUTHOR]

A new compound NaIn 3 S 5 has been obtained in the CaS–In 2 S 3 /NaBr system via a reactive flux method. NaIn 3 S 5 crystallizes in the orthorhombic space group Pbam (No. 55) with a = 12.4963(8) Å, b = 16.0811(10) Å, c = 3.8041(2) Å, and Z = 4. The NaIn 3 S 5 structure is characterized by a three dimensional framework consisting of interconnected tripartite-octahedral [ In 3 S 8 ] ∞ 1 infinite chains, with Na + cations residing in the one-dimensional channels along the c direction defined by S(1), S(2), S(3) and S(4) atoms. The optical reflectance measurement shows a band gap of 2.18 eV for NaIn 3 S 5 . Electronic structure calculation by the CASTEP code not only indicates that NaIn 3 S 5 is an indirect band gap semiconductor, but also explains why its experimental band gap is close to that of β-In 2 S 3 . [ABSTRACT FROM AUTHOR]

Highlights: [•] GO is firstly used as a structure-directing and morphology-controlling template. [•] Composition, structure and morphology of catalysts are controlled by tuning GO amount. [•] 1%G-BMO exhibits excellent photocatalytic activity for RhB degradation. [•] Plausible formation and photocatalytic mechanisms of catalyst are proposed. [Copyright &y& Elsevier]

Ionothermal reaction of NiCl2·6H2O and tetrazole-1-acetic acid (1-Htza) in ionic liquid [BMIM]Br (BMIM=1-butyl-3-methylimidazolium) afforded a new 3D Ni(II) coordination polymer [Ni(1-tza)2]n1. When 2,2′-bipy was introduced, another 1D chained polymer, [Ni(1-tza)(2,2′-bipy)(H2O)2]nXn·2nH2O (2, X=0.78Br+0.22Cl) was acquired. Both compounds have been structurally characterized by single-crystal X-ray diffraction analyses. In the obtained compounds, 1-Htza ligands adopt two different coordination modes: μ3-κN4:κO1:κO2 for 1, and μ2-κN4:κO1 for 2. The temperature-dependent magnetic susceptibilities of 1 and 2 have been measured and theoretically fitted by means of a 1-D chain model. A ferromagnetic interaction between Ni(II) ions exists in 1 with J=3.24cm−1, while an antiferromagnetic interaction in 2 with J=−5.72cm−1. [ABSTRACT FROM AUTHOR]

Abstract: Two polycatenated coordination polymers, {[Zn3(adc)3(bpp)4]2 ·3H2O} n (1) and [Zn(adc)(bphy)] n (2) (adc=azobenzene-4,4′- dicarboxylate, bpp=1,3-bis(4-pyridyl)propane, bphy=1,2-bis(4-pyridyl)hydrazine), have been obtained from Zn(NO3)2∙6H2O, linear H2adc ligand and arched bpp/azpy (azpy=4,4′-azobispyridine) ligands by hydro(solvo)thermal reactions. Compound 1 presents a 2-D structure catenated from 1-D double ladders (1-D→2-D polycatenation), while compound 2 displays a 3-D structure catenated from 2-D (4,4) stair-stepping layers (2-D→3-D polycatenation). Luminescence properties of 1 and 2 have been explored, together with study of photoluminescent mechanism by density of states (DOS) calculation. [Copyright &y& Elsevier]

A 1D solvent-free energetic coordination polymer [Zn 3 (μ 3 -OH) 2 (att) 4 ] n 1 (Hatt = 4-amino-1,2,4-triazole-5-thiol) was obtained and structurally characterized. Compound 1 displays competitive energetic performance and low mechanical sensitivity, which demonstrates 1 has the potential application in insensitive energetic material. [Display omitted] • A new 1D solvent-free energetic coordination polymer [Zn 3 (μ 3 -OH) 2 (att) 4 ] n 1 (Hatt = 4-amino-1,2,4-triazole-5-thiol) was obtained. • The energetic polymer 1 possesses high enthalpy of formation, low mechanical sensitivity and relatively high decomposition temperature. • This work provides an effective method for increasing the oxygen content of energetic compounds. It is a challenge to increase the oxygen content with maintaining the mechanical sensitivity of the energetic materials. In this work, the 1D solvent-free energetic coordination polymer [Zn 3 (μ 3 -OH) 2 (att) 4 ] n 1 (Hatt = 4-amino-1,2,4-triazole-5-thiol) was obtained in alkaline solution through a simple hydrothermal reaction. The X -ray crystallographic analysis indicates that there are two hydroxyl ions embedded in the three Zn(II) atoms through strong coordination bonds, which can provide a strategy for improving the oxygen content of energetic compounds. In addition, the energetic polymer 1 possesses high enthalpy of formation (2012.700 kJ·mol−1), low mechanical sensitivity (IS > 40 J, FS > 360 N) and relatively high decomposition temperature (235 °C). These results demonstrate that compound 1 has the potential application in insensitive energetic material. [ABSTRACT FROM AUTHOR]

Three new diamond-like compounds with the formula of I2−II−IV−VI4 (I=Cu; II=Mg; IV=Si, Ge; VI=S, Se) have been synthesized via traditional high-temperature solid-state reactions and structurally characterized by single crystal X-ray diffraction analysis. All the three compounds crystallize in the space group Pmn21 in the wurtzite-type superstructure with a=7.563(4), b=6.448(3), c=6.179(3)Å, Z=2 for Cu2MgSiS4 (1); a=7.953(5), b=6.797(4), c=6.507(4)Å, Z=2 for Cu2MgGeS4 (2); a=7.638(4), b=6.515(4), c=6.225(3)Å, Z=2 for Cu2MgSiSe4 (3). All atoms in these compounds are tetrahedrally coordinated. Optical diffuse reflectance UV/Vis/NIR spectra indicate that compounds 1 and 2 have the band gaps of 3.20 and 2.36eV, respectively. Electronic structure calculations using the CASTEP code indicate that they are all direct band gap compounds. [ABSTRACT FROM AUTHOR]

A novel open-framework cadmium selenite bromide, [Cd10(SeO3)8Br4]·HBr·H2O (1), has been obtained by a solid-state reaction at 450°C, and the structure has been determined by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in Pbcm of the orthorhombic system: a=10.882(3), b=16.275(5), c=18.728(6)Å, V=3317(2)Å3, R1/wR2=0.0411/0.0659. Compound 1 is characteristic of a novel 3-D open-framework structure, composing ∞ 2[CdSeO3] layers and the pillars of edge-shared CdO3Br2 square pyramids. The lattice water molecules and the HBr molecules locate in the voids of the framework. Optical absorption spectrum of 1 reveals the presence of an optical gap of 1.65eV. Solid-state photoluminescent study indicates that compound 1 exhibits strong violet emission. TG–DSC measurement shows that compound 1 is thermally stable up to 200°C. [ABSTRACT FROM AUTHOR]

The new spiroffite Mg2Te3O8 ( 1) was prepared by hydrothemal methods and structurally characterized by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the space group C2/ c of the monoclinic system with two formula units in a cell: a = 12.6030(7), b = 5.2254(3), c = 11.6331(7) Å, β = 98.6960(10)°, V = 757.30(8) Å3. The structure features a 3D open-framework with spiroffite topology that has large tunnels approximately 3.2 × 5.5 Å. The optical properties and thermal stability of 1 were characterized by UV and IR spectroscopy as well as TG. Calculations of the electronic band structure along with the density of states (DOS) indicate that the present compound is a semiconductor with an indirect band gap, and that the optical absorption is mainly originated from the charge transitions from O-2p state to Te-5p and Te-5s states. [ABSTRACT FROM AUTHOR]

Abstract: Through controlling the temperature, pH value, solvent and added metal salts, six new zinc(II) and cobalt(II) coordination polymers with different structural features, formulated as {[Zn2(HCAM)2(bipy)]·2H2O} n (1), {[Co3(CAM)2(bipy)2·(H2O)4]·16/3H2O} n (2), {[Co(HCAM)(bipy)]·19/6H2O} n (3), {4(H2O)·[Co(bipy)·(H2O)4](bipy)[Co(HCAM)2]} n (4), Zn2(HCAM)2(bipy)·(H2O)2 (5), and 2(H2O)·[Co2(HCAM)2(bipy)·(H2O)4] (6) (bipy=4,4′-bipyridyl), have been synthesized based on reaction between chelidamic acid (2,6-dicarboxy-4-hydroxypyridine, called as H3CAM) and 4,4′-bipyridyl. For 1 and 3, metal ions connected by the carboxylate O atoms to form a one-dimensional chain, which was then further linked by 4,4′-bipyridyl to form 2D coordination polymers. In 2, the Co(II) ions and chelated chelidamic acid ligands are interconnected by the hydroxyl oxygen atom to form a nearly linear chain and are further assembled into a 2D coordination polymer via the [Co(bipy)2·4H2O]2+ units. In 4, there exist a one-dimensional polymeric [Co(C10N2H8)·(H2O)4] n 2+ chain and a discrete [Co(HCAM)2]2− anion, and then further assemble into a 2D supramolecular network via H-bonds and π–π stacking interactions. And compounds 5 and 6 are isostructural and possess discrete structures. The solid-state photoluminescence, magnetic properties and IR of 1–6 have been investigated. [Copyright &y& Elsevier]

Abstract: Hydrothermal reaction of methyl 4-(cyanomethoxy)benzoate, Cd(NO3)2·4H2O and NaN3 yielded a new 2D Cd(II) coordination polymer, {[Cd3(N3)2(mtzb)4(H2O)2]·(H2O)2.5}n 1 (Hmtzb=methyl 4-(1H-tetrazol-5-ylmethoxy)benzoate), which was characterized by single-crystal X-ray diffraction. The in situ [2+3] cycloaddition reaction of nitrile and azide in presence of Cd(II) salt afforded a new tetrazolate-based mtzbˉ ligand. In polymer 1, The cross-linkage of the mtzbˉ ligands and Cd(II) atoms forms a 2D layer network, and the mtzbˉ ligand displays two distinct μ3-bridging coordination modes, μ 3-κN1:κN2:κN3 and μ 3-κN1:κN2:κN4. Photoluminescent analyses revealed that 1 exhibits a strong blue emission with a fluorescent lifetime of 3.22ns. The relevant density of states (DOS) calculation results showed that the photoluminescence mainly originates from ligand-centered charge transition. [Copyright &y& Elsevier]

Abstract: Inorganic–organic hybrids with mixed halo atoms or organically coordinated halometal-complex cations are rare. A series` of haloplumbate hybrids with these structural features, [Cu(phen)2Cl] n (PbCl3) n (phen = 1,10-phenanthroline) (1), [Cu(phen)2Cl] n [PbClI(Cl0.5I0.5)] n (2), and [Cu(phen)2I] n (PbI3) n (3), have been solvothermally synthesized using phen coordinated halocopper(II) complexes as templates and balance cations. Their haloplumbate ions all show 1-D chain structures. Compounds 1–3 feature the hybridization of inorganic–organic hybrids: 1) their absorption edges fall in the range of those of semiconductors, which is typical for bulk lead(II) halides, but show a red shift compared with those of the latter; 2) bulk lead(II) halides are nonluminous upon UV irradiation, but introduction of the phen coordinated halocopper(II) complexes as templates enable the hybrids to emit blue light. Their luminescent intensities gradually decrease with the increase of I content, which indicates the potential to design and syntheses of new luminescent halide materials by means of variation of halo atoms and that iodoplumbates are not good candidates for luminescent materials. [Copyright &y& Elsevier]

Abstract: In our investigation of rare earth sulfides in the AE-RE-Sn-S (AE=alkaline-earth, RE=rare earth) system, three isostructural quaternary sulfides have been obtained. These compounds adopt the Eu5Zr3S12 structure type and crystallize in the P-62m space group (no. 189); the crystal data are as follows: Sr2Y2.67Sn3S12, a =11.600(7)Å, c =3.948(3)Å, Z =1; Ca3La2Sn3S12, a =11.5997(6)Å, c =3.9407(4)Å, Z =1; Ca3Er2Sn3S12, a =11.448(3)Å, c =3.8780(11)Å, Z =1. Single-crystal analysis indicated that the crystal structures consist of three types of building block: RES7, AES6, and SnS6 units. The structure of Sr2Y2.67Sn3S12 is characterized by the trimer-chains along the c direction, which are connected into a 3-dimensional framework by the Sn atoms via S(1), S(2), and S(3), with Sr atoms filling in the channels along the c direction. The optical band gap of 1.45eV for Ca3La2Sn3S12 was deduced from the diffuse reflectance spectrum. [Copyright &y& Elsevier]

Abstract: Two inorganic–organic hybrids, (MPDA)2n (Pb3I10) n (MPDA= p-Me3NC6H4NMe3) (1) and (H2EPDA) n (Pb2I6) n ·2nH2O (H2EPDA= p-Et2NHC6H4NHEt2) (2), have been solvothermally synthesized using p-phenylenediamine (PDA) as a precursor. Their iodoplumbate ions all show 1-D chain structures, but differ in interlinkage modes of [PbI6] octahedra: the former is both face- and edge-sharing, while the latter is face-sharing. The chain-like structure in 1 was reported only once in the literature. The results of optical absorption spectra and theoretical calculations for compounds PbI2 and 1–2 reveal a quantum confinement effect. Photoluminescent analyses show that they all exhibit blue emissions upon UV irradiation, which mainly originate from charge transfer from iodine atoms to ammoniums. [Copyright &y& Elsevier]

Abstract: A new framework compound, [Hg4As2](InBr3.5As0.5) (1), has been prepared by the solid-state reaction of Hg2Br2 with elemental In and As at 450°C. Compound 1 crystallizes in the space group P 63/mmc of the Hexagonal system with two formula units in a cell: a = b =7.7408(6)Å, c =12.5350(19)Å, V =650.47(12)Å3. The crystal structure of 1 features a novel 3D framework, [Hg4As2]2+ with tridymite topology. The optical properties were investigated in terms of the diffuse reflectance and infrared spectra. The electronic band structure along with density of states (DOS) calculated by DFT method indicates that the present compound is semiconductor, and the optical absorption is mainly originated from the charge transitions from Br-4p and As-4p states to Hg-6s and In-5p states. [Copyright &y& Elsevier]

Abstract: Hydrothermal reaction of Cd(NO3)2, Co(NO3)2, Na(3-cba) and NaN3 yielded a 3D heterometallic coordination polymer, [Cd(μ5-3-tzba)(μ2-3-cba)(μ3-OH)Co(H2O)] n ·2nH2O 1 (3-H2tzba=3-(5H-tetrazol)benzoic acid and 3-Hcba=3-cyanobenzoic acid), which was characterized by single-crystal X-ray diffraction. The in situ [2+3] cycloaddition reaction of nitrile and azide in presence of Cd(II) salt afforded tetrazolate-based 3-tzba2− ligand. In 1, metal-oxo chains [Cd(μ3-OH)Co] n are linked by 3-tzba2− in an unprecedented μ5-κN1:κN2:κN3:κN4:κO1,O2 coordination mode to form 2D layers, which are further pillared by 3-cba− to generate a 3D open framework encapsulating 1D chiral channels. Variable-temperature magnetic studies show that 1 exhibits antiferromagnetic interactions between Co(II) ions bridged by μ3-OH group. [Copyright &y& Elsevier]

Abstract: Hydrothermal reaction of 1H-tetrazolate-5-ethyl acetate (Htzea), MCl2 (M=Zn, Cd) and NaOH at different reaction temperatures produced three new coordination polymers: 2-D layered polymer [Zn(tza)(H2O)2] n 1, and 1-D chained supramolecular isomers 2 and 3 formulated as [Cd(tza)(H2O)2] n (H2tza=1H-tetrazolate-5-acetic acid), respectively. In these obtained polymers, tza2− ligand adopts variable coordination modes: μ 3-κN3:κO1:κO2,N1 and μ 3-κN1:κN3:κO2 for 1, and μ 3-κN2:κN1,O2:κO1,O2 for 2 and 3. The effects of reaction temperature and metal centers on the final polymeric frameworks have been discussed. Polymers 1–3 exhibit blue photoluminescence mainly arising from intraligand transitions of tetrazolate rings in tza2− ligand. [Copyright &y& Elsevier]

Abstract: A 1D coordination polymer, {[Cu3(C7H2NO5)2(H2O)7]·2(H2O)} n (1), has been synthesized and characterized by X-ray single-crystal diffraction. The crystal structure of 1 features that distorted square–pyramidal coordination polyhedra composed of Cu atoms and chelidamic acid ligands are interlinked into a 1D polymer, further linked by hydrogen bonds into a 3D network. The optical properties were investigated in terms of diffuse reflectance and fluorescent spectra, which exhibit strong luminescence. The electronic band structure along with the density of states (DOSs) calculated by the DFT method indicate that compound 1 pose an energy band gap of 1.89eV and that the origin of the emission band may be mainly ascribed to metal-to-ligand charge transfer (MLCT) where the electrons are transferred from the Cu-3d to O-2p and C-2p states. [Copyright &y& Elsevier]

Abstract: A new supramolecular complex [Hg6Sb4](InBr6)Br (1) has been prepared by the solid-state reaction of HgBr 2 with elemental In and Sb at 450°C. The crystal structure of 1 features a three-dimensional [Hg6Sb4]4+ framework with cavities of two different sizes occupied by different kinds of guest anions. The bigger cavities are filled with the octahedral InBr6 3− ions, while the smaller cavities trap Br− ions. The optical properties were investigated in terms of the diffuse reflectance and infrared spectra. The electronic band structure along with density of states (DOS) calculated by DFT method indicates that the present compound is semiconductor, and the optical absorption is mainly originated from the charge transitions from Sb-5p and Br-4p to In-5s and Hg-6s states. [Copyright &y& Elsevier]

Abstract: The reaction of Zn(II) ions and chelidamic acid (2,6-dicarboxy-4-hydroxypyridine) gave a novel 1D coordination polymer, [Zn3(C7H2NO5)2·8(H2O)] n (1), which are characterized by X-ray single crystal diffraction. The crystal structure of 1 reveals that Zn(II) centers are linked via chelidamic acid to form one-dimensional chains, further linked by hydrogen bonds to form a 3-D network. The optical properties were investigated in terms of diffuse reflectance and fluorescent spectra, which exhibit strong green luminescence. The electronic band structure along with the density of states (DOS) calculated by the DFT method indicate that compound 1 is a semiconductor and that the origin of the emission band may be mainly ascribed to ligand-to-ligand charge transfer (LLCT) where the electrons are transferred from the O-2p to C-2p states. [Copyright &y& Elsevier]

Abstract: Three new 4-cyanobenzoate coordination complexes have been prepared, and their structures have been characterized by single-crystal X-ray diffraction. In [Cd(4-cba)2(py)2(H2O)] 1 and [Mn(4-cba)2(phen)(H2O)2] 2 (4-Hcba=4-cyanobenzoic acid, py=pyridine, phen=1 10-phenanthroline), carboxylate groups exhibit chelated bidentate and terminal monodentate coordination modes, respectively, to give discrete mononuclear units, which are linked by hydrogen bonds and face-to-face π−π stacking interactions to produce a 2-D supramolecular network. In [Mn(4- cba)2(H2O)2]n 3, the Mn(II) atoms are bridged by carboxylate groups of 4-cba ligands in the syn-skew bidentate mode in two directions to form a 2-D grid-like framework with a (4,4) topology, and there also exist hydrogen bonds and face-to-face π–π stacking interactions in the layers. Variable-temperature magnetic susceptibility data show the presence of weak antiferromagnetic interactions with θ =−1.13(5)K in 2 and significant antiferromagnetic ordering (T N =7.0K) with θ =−11.40(5)K in 3. The thermogravimetric analyses of the three complexes have also been discussed. [Copyright &y& Elsevier]

Abstract: The reaction of double betaine ligand L1 (L1 =1,3-bis(pyridinio-4-carboxylato)-propane) with Cu(ClO4)2 and Cu(NO3)2, respectively, afforded two novel anion-directed coordination polymers with different open frameworks. The structure of [Cu3(L1)2(OH)2(H2O)2](ClO4)4·2H2O 1 is a unique 3-D open-framework with large S-shape channels, while [Cu3(L1)2(OH)2(H2O)2](NO3)4·2H2O 2 has a 2-D tubular structure. There exist inorganic copper-oxo chains [Cu3(μ3–OH)2(μ2–H2O)2] n in both 1 and 2 as secondary building units, in which the [Cu3O4] cores exhibit a rarely observed chair-like configuration. The anion template of and , and labile coordination orientation of L1 ligand prompt the formation of different polymeric networks in 1 and 2. [Copyright &y& Elsevier]

Abstract: Two new Cu(II) coordination polymers with double betaine ligands have been prepared, and their structures have been characterized by single-crystal X-ray diffraction techniques. The structure of [Cu(L1)2](ClO4)2·2H2O 1 (L1 =1,3-bis(pyridinio-4-carboxylato)-propane) contains 1-D cationic chains, in which the adjacent Cu(II) atoms are doubly bridged by L1 ligands in the syn-syn bis-monodentate mode. In [Cu(L2)2](ClO4)2·4H2O 2 (L2 =1,4-bis(pyridinio-4-carboxylato)-1,4-dimenthylbenzene), the Cu(II) atoms are joined by the L2 ligands in the same coordination mode as 1 in two directions to form a 2-D grid-like framework. The crystal packing in 1 and 2 is controlled mainly by face-to-face π–π stacking interactions between pyridine rings. The thermal stability of 1 has also been investigated. [Copyright &y& Elsevier]

Abstract: High-quality single crystals of RbInS2, CsInS2 were isolated from the halide flux as a major phase of the repeated fusion of CaS and In2S3 followed by slow cooling. RbInS2 and CsInS2 are practically isostructural with KInS2. RbInS2: C2/c, a =11.071(6)Å, b =11.068(1)Å, c =15.610(7)Å, β =100.36(3)°, V =1882(2)Å3, Z =16, d x =3.74g/cm3, R =6.38%, R w =6.42%. CsInS2: C2/c, a =11.197(3)Å, b =11.158(3)Å, c =16.358(4)Å, β =99.92(2)°, V =2013(2)Å3, Z =16, d x =4.12g/cm3, R =5.60%, R w =6.20%. The AInS2 (A=Rb, Cs) structure is characterized by double layers of vertex-sharing [In4S10] units that each consists of four [InS4] polyhedra. The charge-balancing alkali-metal cations are stuffed into the channels created by the packing of these anionic [In4S10] blocks. The optical reflectance measurements show a band gap of 3.3eV for RbInS2 and 3.4eV for CsInS2, suggesting that both are semiconductors. [Copyright &y& Elsevier]

Abstract: Two isostructural metal chalcogenides, Hg2Te2Br2 (1) and Hg2Te2I2 (2), were obtained by solid-state reactions and structurally characterized. Compounds 1 and 2 crystallize in the acentric space group P43212 of the tetragonal system with eight formula units in a cell: a=10.2388(9), c=14.480(2)Å, V=1518.0(3)Å3, R 1/wR 2=0.0670/0.1328 for 1 and a=10.711(3), c=15.025(8)Å, V=1724(1)Å3, R 1/wR 2=0.0637/0.1233 for 2. Both compounds are characterized by a three-dimensional (3-D) framework structure, which is composed by interconnected left-handed helices formed by both tetrahedral and trigonal Hg atoms. Optical absorption spectra of 1 and 2 reveal the presence of sharp optical gaps of 2.06 and 1.85eV, respectively, suggesting that both materials are semiconductors. TG-DTA measurements show that both compounds are thermally stable up to 200°C. The composition of both compounds is well confirmed by the semiquantitative microscope analyses. [Copyright &y& Elsevier]

Abstract: The first structurally characterized orotato samarium(III) complex, [Sm2(HL)2(ox)(H2O)2] n ·2.5nH2O (1), with a novel bi-layered structure has been synthesized and structurally characterized by X-ray crystallography, in which orotic acid ligands exhibit two coordination modes of μ3-η2κO,O′:η2κO′,N:η1κ″ and μ4-η2κO,O′:η2κO′,N:η1κ″:η1κO‴ for HL2− with the latter being novel coordination mode. The temperature dependence of the magnetic susceptibilities of the title complex reveals that the title complex follow the Curie–Wiess paramagnetic behavior down to 5K. The title complex exhibits strong luminescent emissions based on the f–f transitions of Sm(III) ion and 4G5/2 lifetime. [Copyright &y& Elsevier]

Abstract: Three new zinc coordination polymers [Zn2(btc)2(H2O)2] n ·n[Zn(H2O)6] (1), [Zn3(btc)2(2,2′-bipy)2(H2O)3] n ·2nH2O (2) and [Zn3(btc)2(H2O)6] n ·nH2O (3) (H3btc=1,2,4-benzenetricarboxylic acid, 2,2′-bipy=2,2′-bipyridine) were obtained by the diffusion method and their crystal structures were determined by single-crystal X-ray diffraction. Compounds 1–3 have the similar tetrametallic unit [Zn4(btc)2] SBUs and these SBUs are further connected into stair-like structure, 2-D layer and 3-D framework for 1, 2 and 3, in which the btc3− ligands adopt μ 3, μ 4 and μ 5 coordination modes, respectively. The title compounds show strong blue fluorescence, which may be assigned as π*→n transition of the ligand mixed with the ligand-to-metal change transfer (LMCT), indicating the fluorescence, indicates the title compounds may be good candidates for blue-light photoactive materials. [Copyright &y& Elsevier]