Hydrothermal Synthesis of Brucite Type Copper Hydroxide Squarate [Cu3(OH)2(C4O4)]·4H2O

Herein we report synthesis of a new brucite type copper hydroxide squarate, Cu₃(OH)₂(C₄O₄)₂·4H₂O [P2₁/c, a = 5.6437(4) Å, b = 12.8357(9) Å, c = 9.1507(6) Å, β = 95.892(1)° and Z = 2] by hydrothermal method, and its characterization by single crystal diffraction analysis as well as by IR spectroscopy. The rather wide spread of Cu–O bond lengths, can be primarily rationalised by the Jahn‐Teller effect, and secondarily by the connectivities of the CuO₆ octahedra.     

Synthesis and Structure of Lithium Cadmium Selenite Hydroxide,LiCd2(SeO3)2(OH)

The new compound LiCd₂(SeO₃)₂(OH) has been hydrothermally synthesized and characterized by single‐crystal X‐ray diffraction and IR spectroscopy. It is built up from a network of edge‐ and vertex‐sharing pyramidal [SeO₃]^2— groups, distorted CdO₆ octahedra, and CdO₇ monocapped trigonal prisms. The cadmium‐centred groups form infinite columns, onto which Se atoms (as [SeO₃]^2— groups) are grafted. Cross‐linking between the columns results in a three‐dimensional framework which encapsulates [100] channels occupied by the tetrahedrally‐coordinated lithium cations. The H atom of the hydroxyl group appears to participate in a weak, bifurcated, hydrogen bond. Crystal data: LiCd₂(SeO₃)₂(OH), M_r = 502.67, monoclinic, P2₁/c (No. 14), a = 5.8184 (3)Å, b = 10.2790 (5)Å, c = 11.5021 (5)Å, β = 90.446(1)°, V = 687.89 (9)ų, Z = 4, R(F) = 0.021, wR(F²) = 0.046.     

A new orthoborate,Sr3Ga3(BO3)4O(OH)

The crystal structure of tristrontium trigallium tetraborate oxide hydro­xide has been determined by X‐ray diffraction using a crystal grown by hydro­thermal crystallization of a strontium gallo‐borate glass. It represents a new orthoborate structure type built of complex layers formed by BO₃ triangles sharing corners with Ga₂O₇ tetrahedral dimers and GaO₄OH square pyramids. The Sr atoms occupy both inter‐ and intralayer sites.     

Synthesis and properties of stereoregular cyclic polysilanols: cis-[PhSi(O)OH](4), cis-[PhSi(O)OH](6), and tris-cis-tris-trans-[PhSi(O)OH](12)

New stereoregular cyclic polysilanols of the general formula [PhSi(O)OH]n (n = 6 and 12) have been selectively obtained in high yields by the reaction of cagelike oligophenylmetallasiloxanes with dilute solutions of hydrochloric acid at low temperatures. An alternative method was used to prepare cis-[PhSi(O)OH](4) from sodium phenylsiloxanolate, cis-[(Na(+))(4)[PhSi(O)O(-)](4)].(1-butanol)(x). All compounds were fully characterized by NMR and IR spectroscopy and molecular weight determinations. The structure of cis-[PhSi(O)OH](6) was confirmed by single-crystal X-ray analysis. Furthermore, a series of stereoregular cyclosiloxanes containing triorganylsiloxy groups at each silicon atom was prepared by the reactions of the cyclic polysilanols with triorganylchlorosilanes Me(3)SiCl, Me(2)ViSiCl, and Me(2)(CH(2)Cl)SiCl.     

仲钨酸盐A柱撑化合物Mg12Al6(OH)36(W7O24)·4H2O的合成及其光催化性能研究

光催化降解水中有机污染物并使之矿化为无机物的技术正在引起众多学者的关注[1～3]. 目前, 两类主要的光催化剂为半导体金属氧簇和多金属氧酸盐簇(POM). 然而, 这两类催化剂在使用过程中都存在着催化剂难以回收的缺点. 将POM嵌入层柱双氢氧化物(LDH)中制备POM柱撑化合物是固载POM的有效途径之一[4]. 均相体系中仲钨酸盐A(W7O6-24)的光化学活性已有研究, 它可使22种卤代烃完全降解和矿化[5]. 本文通过阴离子交换反应制备了水不溶性的仲钨酸盐A柱撑化合物Mg12Al6(OH)36(W7O24)*4H2O(缩为Mg2Al-W7), 所用前躯体为Mg4Al2(OH)12TA*xH2O (简写为Mg2Al-TA, TA2-= 对苯二甲酸根离子). Mg2Al-W7在非均相体系中的光化学行为通过水溶液中有机氯杀虫剂六六六(C6H6Cl6, 用HCH表示)的降解与矿化进行了研究. 据报道, 由于六六六非常稳定和难于降解, 目前农田中仍存在数以千吨计的残留的六六六, 国外文献近期仍在报道TiO2光催化降解六六六的方法[6,7]. 我们的研究表明, Mg2Al-W7对降解及矿化六六六有活性, 且催化剂易于分离回收, 并可用于再循环. 这些特点为Mg2Al-W7光催化降解水中其它有机污染物的研究与应用奠定了基础.     

[HN(C2H5)3][B5O6(OH)4]的合成、结构和热稳定性

利用水热法合成了五硼酸三乙胺[HN(C2H5)3][B5O6(OH)4], 并利用单晶X射线衍射技术解析了其结构, 同时利用傅立叶红外分析、元素分析及热分析技术加以佐证. 该化合物属于单斜晶系, 其空间群为P21/c, 相应的晶胞参数为a=1.0036(2) nm, b=1.1353(2) nm, c=1.4843(3) nm和β=106.54(3)°. 它由孤立的五硼酸阴离子[B5O6(OH)4]-和三乙胺阳离子[HN(C2H5)3]+构成. 五硼酸阴离子[B5O6(OH)4]-通过氢键构成三维网状结构, [HN(C2H5)3]+位于其中的孔道中.     

Co(en)3[B4O5(OH)4]Cl·3H2O和[Ni(en)3][B5O6(OH)4]2·2H2O的合成、结构以及热力学性质

利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。     

Synthesis and structure of asymmetric zirconium-substituted silicotungstates, [Zr6O2(OH)4(H2O)3(beta-SiW10O37)3]14- and [Zr4O2(OH)2(H2O)4(beta-SiW10O37)2]10-

The reaction of ZrCl4 with [gamma-SiW10O36]8- in a potassium acetate buffer results in two different products depending on the reactant ratios. The trimeric species [Zr6O2(OH)4(H2O)3(beta-SiW10O37)3]14- (1) consists of three beta23-SiW10O37 units linked by an unprecedented Zr6O2(OH)4(H2O)3 cluster with C1 point group symmetry. The dimeric species [Zr4O2(OH)2(H2O)4(beta-SiW10O37)2]10- (2) consists of beta22- and beta12-SiW10O37 units sandwiching a Zr4O2(OH)2(H2O)4 cluster, which also has C1 symmetry. Polyanion 1 contains more zirconium centers than any other polyoxometalate known to date.     

N(nPr)4[B5O6(OH)4][B(OH)3]2 and N(nBu)4[B5O6(OH)4][B(OH)3]2: Clathrates with a diamondoid arrangement of hydrogen-bonded pentaborate anions

Single-crystal X-ray structure analyses of N(nPr)₄[B₅O₆(OH)₄][B(OH)₃]₂,1, and N(nBu)₄ [B₅O₆(OH)₄][B(OH)₃]₂,2, reveal that these materials are novel clathrates, the isotypic host structures of which are three-dimensional assemblies of hydrogen-bonded [B₅O₆(OH)₄]^– ionsand B(OH)₃ molecules. The assembly of only the pentaborate anions is a distorted (i.e., along [102] elongated) fourconnected diamond-related network. The N(nPr) ₄ ⁺ and N(nBu) ₄ ⁺ ions are trapped within the complex three-dimensional channel systems of the host frameworks. Both1 and2 crystallize monoclinically with space groupP2₁/c andZ=4. The cell constants are:1:a=13.592(5),b=12.082(2),c=17.355(6) Å, =106.60(2)° (298K);2:a=13.874(3),b=12.585(1),c=17.588(4) Å, =107.04(1)° (238 K). The results obtained by both¹¹B and¹³C MAS NMR spectroscopy are discussed. Thermogravimetric studies under a flowing inert-gas atmosphere suggest that water, stemming from polycondensation of the hydrous borate species, is released from the clathrates at ca. 443 K (1) and 398 K (2) before the decomposition of the organic cations starts at ca. 603 K (1) and 603 K (2).Author for correspondence. Supplementary Data relating to this article are deposited with the British Library as supplementary publication No. SUP 82172 (82 pages).     

BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合光催化剂的制备及光催化性能研究

以Bi(NO_3)_3·5H_2O和NH_4VO_3为原料,控制水溶液介质p H及反应时间,采用水热合成法制备钒酸铋(BiVO_4)及其复合物(BiVO_4/Bi_6O_6(OH)_3(NO_3)_3).利用X-射线粉末衍射、扫描电子显微镜和紫外-可见漫反射吸收光谱等手段对制备的样品进行了物理表征,结果表明,在控制反应时间为1 h,介质p H值在1.14~9.01之间时,制备的样品为BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合物,当p H值增加至10.92时为纯BiVO_4;控制介质p H为7.17,反应时间在1~12 h之间时得到BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合光催化剂,反应时间为18 h时为纯BiVO_4.在可见光(λ≥400 nm)照射下,以有机染料罗丹明B(Rhodamine B,Rh B)为底物,研究不同条件制备的BiVO_4或者复合物为光催化剂的光催化特性,发现p H=7.17,水热反应12 h得到的催化剂(BiVO_4/Bi_6O_6(OH)_3(NO_3)_3)光催化降解活性高于对照制备的纯BiVO_4.同时在可见光照射下,BiVO_4/Bi_6O_6(OH)_3(NO_3)_3亦可以有效降解无色小分子2,4-二氯苯酚(2,4-Dichlorophenol,2,4-DCP),说明氧化过程涉及到光催化过程.分析BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合光催化剂对Rh B光催化降解过程中活性物种,表明在降解过程中主要涉及空穴和超氧氧化,O_2·~-起主要作用.     

The First Gallium Borophosphate NaGa[BP2O7(OH)3]:Synthesis and Crystal Structure Characterization

Borophosphates, as potential microporous materials, have drawn much attention in recent years and show rich chemistry^[1-3]. Although many compounds with transition metals have been reported, compounds with the p-block main group elements participating in the framework are rare^[4] The title compound has been synthesized by mild hydrothermal methods and crystal structure characterized by X-ray single crystal methods. Crystallographic data:monoclinic,C2/c (No. 15), a=10.408(3), b=8.094(2),c=9.099(2) Å, β=116.64(2), Z=4, R=0.0246,Rw=0.0676. The crystal structure contains isolated anions[(OH)O₂P_1/2-O_1/2B(OH)₂O_1/2-O_1/2PO₃]^4-. Geometrically, four GaO₆ groups with four PO₄ groups form an eight-member ring by sharing comers resulting to a two dimensional layer in be plane. The layers are joined by BO₄ group through comer sharing with GaO₆ and PO₄ and result to a three dimensional network structure. A 350pm x 600pm open channel along c-axis can be seen (figure below) and occupied by Na cations.