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The synthesis and crystal structure characterization of a new nonlinear optical crystal material [Cd.sub.4]BiO[(B[O.sub.3]).sub.3] with 3-chromophore asymmetric structures of Cd[O.sub.n], Bi[O.sub.6], and B[O.sub.3] groups is presented. The properties of crystal complex such as large SHG effect, phase-match, and high thermal stability could find potential use in industrial production and applications for [Cd.sub.4]BiO[(B[O.sub.3]).sub.3].

Twogenuine supramolecular isomers [Co(1,4-NDC)(5,5'-dmbpy)]n(1αand 1β) and compound {[Co(1,4-NDC)(5,5'-dmbpy)(H2O)2]2}n(2) (1,4-NDCH2= 1,4-naphthalenedicarboxylic acid, 5,5'-dmbpy= 5,5'-dimethyl-2,2'-dipyridyl) have been synthesizedunder conventional hydro(solvo)thermal reactions. The highly crystallinesingle-phases of 1βand 2with a well-definedmorphology could also be quickly prepared through microwave-assistedsyntheses within 5 min. Compared with 2, which possessesa one-dimensional (1D) single-chain-like structure, 1αand 1βfeature the structures of 1D ladder-likechain and two-dimensional (2D) layer, respectively, constructed fromthe ring-like [Co2(OOCR)2] dimeric units interlinkedby the 1,4-NDC ligands. The drastic structural transformation from 1αto 2, as well as the interconversionbetween 1βand 2, was observed, whichinvolved the reversible destruction and reconstruction of the Co2(OOCR)2unit during the transformation and wasassociated with remarkable changes in magnetic properties. Remarkably, microwave heating as an external driving force was adopted to achievestructure transformation from 2to 1βwithin 5 min. This work demonstrates that the microwave techniquecan be used as a quick and efficient synthetic method to investigatethe structural conversion between compounds and further bring aboutproperty modulation. [ABSTRACT FROM AUTHOR]

Low-dimensional mixed anion compounds Ba18F18In8S21 (1) and Barf10In4S10 (2), are synthesized and characterized. These compounds crystallize in the space group P42/ncm(138) with a = b = 22.0703(8) Å, c = 12.6143(9) Å, and V = 6144.4(6) Å3 (Z = 4) for 1 and Pnma(62) with a = 12.5686(8) Å, b = 19.2822(12) Å, c = 12.5835(9) Å, and V = 3049.6(3) Å3 (Z = 4) for 2. Compound 1 contains the unusual one-dimensional fluorite type [Ba16F18] ionic region and [BaIn8S21] covalent region, whereas 2 has a two-dimensional fluorite type [Ba2F2] block and the unique tetranuclear [In4S10]8- anion. The first principles electronic structure calculation performed with density functional theory (DFT) indicates that the two compounds are both direct band semiconductors with a gap of 2.28 eV for 1 and 2.23 eV for 2. [ABSTRACT FROM AUTHOR]

A new polymorph of copper(II) vanadate, Cu2(VO4)(OH), containing a layered magnetic sublattice, is synthesized by a hydrothermal reaction. It displays a 3D framework based on copper(II) oxide layers which are further connected by VOu4 tetrahedra through corner-sharing {V-O-Cu} bonds in the system. The copper(II) oxide layer is constructed by the interactions of Cu3(μ3-OH) building units. Magnetic properties are investigated by means of magnetic susceptibility, magnetization and heat capacity measurements. The results indicate a typical long-range canted antiferromagnetic ordering below ~10 K and weak spin frustration arising from the competition between antiferromagnetic and ferromagnetic interactions inside the irregular Cu3(μ3-OH) triangles. [ABSTRACT FROM AUTHOR]

We present here the structures and magnetism of two quasi-1D linear chain compounds of BiM2BP2O10 (M = Co, Ni), which were synthesized by traditional solid-state reactions for the first time. Two title compounds crystallize in the monoclinic system with space group P21/c and feature novel 3D structures with a linear chain structure of (MO6}n further connected by [BP2O10]7- anionic groups. The results of magnetic property measurements evidence the antiferro-magnetic properties of both compounds in low magnetic field and a field-dependent metamagnetic transition from the antiferromagnetic to ferromagnetic ground state of the BiCo2BP2O10 complex. [ABSTRACT FROM AUTHOR]

Two new quaternary thioborates, PbSbBS4and PbBiBS4, have been synthesized from solid-state reaction methods at temperatures from 1073 to 1123 K in evacuated sealed quartz tubes. The crystal structures have been determined by means of single crystal X-ray diffraction and they both crystallize in the P21/mspace group of the monoclinic system with a= 5.9532(18) Å, b= 6.2031(13) Å, c= 9.250(3) Å, β= 108.200(16)°, Z= 2 for PbSbBS4and a= 5.971(10) Å, b= 6.273(9) Å, c= 9.132(15) Å, β= 107.75(2)°, Z= 2 for PbBiBS4, respectively. The two compounds are isostructural and both constructed with the infinite one-dimensional [MBS4]2−(M = Sb or Bi) chains as building blocks, which are composed of [BS3]3−trigonal plane units with [MS3]3−(M = Sb or Bi) trigonal pyramids connected alternatively through corner-sharing along the crystallographic baxis. Two adjacent [MBS4]2−chains are further bridged by the intermediate Pb2+cations, forming a novel S-shaped Pb-[MBS4] dimeric chain structure. In addition, first-principles electronic structure calculations based on the density functional theory (DFT) were performed on compound PbSbBS4, indicating that the compound belongs to direct semiconductor with a band gap of 1.803 eV, which is in good agreement with the experimental value estimated from the UV-Vis diffuse reflectance spectroscopy. [ABSTRACT FROM AUTHOR]

The magnetic structure of the spin-chain antiferromagnet SrCo2V2O8 is determined by single-crystal neutron diffraction experiment. The system undergoes a long-range magnetic order below the critical temperature TN = 4.96 K. The moment of 2.16μB per Co at 1.6 K in the screw chain running along the c axis alternates in the c axis. The moments of neighboring screw chains are arranged antiferromagnetically along one in-plane axis and ferromagnetically along the other in-plane axis. This magnetic configuration breaks the four-fold symmetry of the tetragonal crystal structure and leads to two equally populated magnetic twins with the antiferromagnetic vector in the a or b axis. The very similar magnetic state to the isostructural BaCo2V2O8 warrants SrCo2V2O8 as another interesting half-integer spin-chain antiferromagnet for investigation on quantum antiferromagnetism. [ABSTRACT FROM AUTHOR]

Two new mid-infrared transparency compounds, centric Ba2BiGaS5 (1) and acentric Ba2BiInS5 (2), were synthesized from a high-temperature solid-state reaction in evacuated closed silica tubes. Their crystal structures were determined by a single crystal X-ray diffraction method at 293 K. The results of crystal structure solution indicate that compound 1 crystallizes in the centrosymmetric space group Pnma with trans-1∞[BiGaS5]4- chain structure, while compound 2 crystallizes in the noncentrosymmetric polar space group Cmc21 with cis-1∞[BiInS5]4- chain structure. Two types of lone-pair electrons alignment fashions within 1∞[BiMS5]4- chains result in destructive (for 1) or constructive (for 2) dipole moments, as illustrated in the crystal structures and the partial electron density maps based on the first-principles electronic structure computations. Powder second-harmonic generation (SHG) experiments with a 2.05 μm pumping laser show that the SHG efficiency of the polar compound 2 is approximately 0.8 times that of KTiOPO4 (KTP) reference. Furthermore, SHG signal intensity measurements using different size particles of powder samples indicate that compound 2 can also achieve type I phase-matching, which makes the compound promising for practical applications. [ABSTRACT FROM AUTHOR]

The article focuses on a study about the synthesis and nonlinear optical (NLO) property of Cd4BiO(BO3)3 compound. It states that stoichiometric mixtures of Bi2O3, CdO, and H3BO3 and crystallographic analysis were conducted in the study. Findings show that mixings among the Bi-6s,-6p orbitals and ligand O-2p orbitals result to the stereochemically active lone pair (SCALP) effect of the Bi3+ cation.