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1.
The crystal structure of the new synthetic compound Ba5[B20O33(OH)4] ? H2O was established by the methods of X-ray diffraction (a Stoe IPDS diffractometer, λMoK α?, 1860 independent reflections, anisotropic refinement, R = 1.95%, localization of hydrogen atoms): a = 9.495(2) Å, b = 6.713(1) Å, c = 11.709(2) Å, β = 95.09(1)°, sp. gr. P2, Z = 1. The structure is based on double pseudohexagonal layers consisting of BO4-tetrahedra and BO3 triangles linked into three-membered rings in two mutually perpendicular directions. The double layers adjacent along the [100] direction are linked together through the Ba-polyhedra and hydrogen bonds with the participation of the OH-groups occupying the “end” vertices of two B-triangles. The interlayer space is also filled with a sheet of Ba-polyhedra. The structure of the compound is compared to the structures of topologically similar Ba and Ca borates and hydroborates.  相似文献   

2.
A new rubidium pentaborate is synthesized under hydrothermal conditions. Its crystal structure is studied by the heavy-atom method without any a priori knowledge of chemical formula. The chemical formula is Rb[B5O6(OH)4] · 0.5H2O, sp. gr. $\bar P1$ , lattice parameters a = 7.679(4) Å, b = 9.253(6) Å, c = 12.053(9) Å, α = 98.55(5)°, β = 106.80(5)°, γ = 91.71°, R = 0.0573, R w = 0.0638, S = 1.07. The anionic part of the structure consists of a chain of fundamental building blocks 5:[4Δ + 1T] built by four B triangles bound to one B tetrahedron, which are common to Na, K, Rb, and Cs pentaborates. This new pentaborate is closely related to the mineral larderellite (NH4)[B5O6(OH)4] · H2O but possesses an original structure, which manifests itself in the different morphology of the new pentaborate and the absence of perfect cleavage. The Dornberger-Schiff OD theory allows one to describe in detail the structural relationships, predict possible hypothetical structures, and write the OD groupoid.  相似文献   

3.
[La(OH2)5(phen)2]Cl3·4H2O·phen is centric, Pnna, witha=19.946(7),b=16.458(5),c=12.207(4)Å andD calc=1.57 g cm–3 forZ=4. The La(III) ion resides on a crystallographic twofold axis and is coordinated to four nitrogen atoms (from two phen molecules) and five water molecules resulting in a distorted tricapped trigonal prismatic geometry. An uncoordinated phen molecule, two chloride anions, and four uncoordinated water molecules are hydrogen bonded to the coordinated water molecules. The coordinated and uncoordinated phen molecules -stack diagonally through the unit cell.  相似文献   

4.
Four Cu(II) complexes with the RR,SS-Edds 4? and SS-HEdds 3? anions are synthesized, and their crystal structures are studied. In the compounds [Cu2(RR,SS-Edds)] · 6H2O (I) and Ba2[Cu(RR,SS-Edds)](ClO4)2 · 8H2O (II), the ligand forms hexacoordinate chelate [Cu(Edds)]2? complexes with the N atoms and O atoms of the propionate groups in the equatorial positions and the O atoms of the acetate groups in the axial vertices. In the compounds Ba[Cu(SS-HEdds)]ClO4 · 2H2O (III) and Ba3[Cu2(RR,SS-Edds)2](ClO4)2 · 6H2O (IV), one of the propionate arms, the protonated arm in III and the deprotonated arm in IV, does not enter into the coordination sphere of the Cu atom. An acetate arm moves to its position in the equatorial plane, and the free axial vertex is occupied by an O atom of the perchlorate ion. In I–IV, the lengths of the equatorial Cu-N and Cu-O bonds fall in the ranges 1.970–2.014 and 1.921–1.970 Å, respectively. The axial Cu-O bonds with the acetate groups and ClO 4 ? anions are elongated to 2.293–2.500 and 2.727–2.992 Å, respectively. In structure I, the second Cu atom acts as a counterion forming bonds with the O atoms of two water molecules and three O atoms of the Edds ligands. In II–IV, the Ba2+ cations are hydrated and bound to the O atoms of the anionic complexes and (except for one of the cations in IV) ClO 4 ? anions. The coordination number of the Ba cations is nine. The structural units in I–IV are connected into layers. In I, an extended system of hydrogen bonds links the layers into a framework. In II and III, the layers are linked only by weak hydrogen bonds, one bond per structural unit. In IV, ClO 4 ? anions are bound to the Ba and Cu atoms of neighboring layers, thus serving as bridges between the layers.  相似文献   

5.
[Sr(C4H2O4)(OH2)3]·H2O is monoclinic, P21/n, witha=11.476(2),b=7.027(1),c=12.344(2) Å, =115.74(3)°,V=896.67 Å3,Z=4. The Sr atom is surrounded by nine oxygen atoms which come from four different maleate anions and three water molecules. The Sr–O distances range from 2.546(2) to 2.808(2) Å. The C–O distances are equal within the standard deviation 1.263(3) to 1.258(3) Å). In the maleate anion, the planes that contain the carboxylate groups form an angle of 74.44(9)°. Both carboxylate groups deviate significantly from planarity. The different coordination modes of the carboxylate group and the extensive hydrogen bonding present are responsible for the polymeric nature of the structure.  相似文献   

6.
Crystals of a new aqueous rare earth borate Sm3[B13O22(OH)3](OH) · 3H2O, space group P2/c, are obtained under hydrothermal conditions. The structure is determined by the heavy-atom method without preliminary knowledge of the chemical formula. The anionic radical is a boron-oxygen sheet in which two corrugated layers are related by centers of inversion. An independent layer is akin to pentaborate layers; it differs from the layer in (Nd0.925Na0.075)Nd[B9O15(OH)2]Cl0.85 · 2.65H2O by an additional branch in the form of a 4: (3[2?? + 1T] + 1??) group. The intersheet space and large holes of the sheet accommodate Sm atoms, (OH) groups, and water molecules. The new Sm-borate and the related Nd-borate are polyborates (megaborates) with complex anionic radicals. In the Sm-borate, the new two-dimensional [B13O22(OH)3]??? complex anionic radical of the 13{(4: [2T + 2??])?? + (5: [3T + 2??] + 4: (3[2?? + 1T] +1??))??}??? formula is built of three different blocks, unlike the [B9O15(OH)2]??? radical of the 9{(4: [2T + 2??])?? + (5: [3T + 2??])??}??? formula in the Nd-borate, which consists of two blocks. The rule of the inverse relationship between the polymerization degrees of the boron-oxygen radical and rare earth polyhedra holds for both borates.  相似文献   

7.
The title complex, [Co(phen)(H2O)4](SO4)2(H2O) (phen = 1,10-phenanthroline) was prepared in aqua tert-butylperoxohydrogen solution. X-ray single crystal structure determination reveals that the complex consists of a phenanthrolinatocobalt(II)tetrahydrate dication, two uncoordinated water molecules and a sulfate anion. It crystallizes in the orthorhombic space group Pbca with a = 8.856(1), b = 18.318(3), c =21.918(5) Å, V = 3555.6(11) Å3. The coordination geometry at each cobalt(II) atom is a slightly distorted octahedron.  相似文献   

8.
Malonate-thiocyanate complex (NH4)3[UO2(C3H2O4)2(NCS)] · 2H2O is synthesized and studied by X-ray diffraction. The compound crystallizes in the monoclinic system: a = 13.9983(4) Å, b = 8.1947(2) Å, c = 16.4678(4) Å, β = 100.846(1)°, space group Cc, Z = 4, and R = 0.0158. The main structural units of the crystal are mononuclear [UO2(C3H2O4)2(NCS)]3? groups belonging to the AB 2 01 M 1 crystal chemical group of uranyl complexes (A = UO 2 2+ , B 01 = C3H2O 4 2? , M 1 = NCS?). Discrete uranium-containing groups are connected by electrostatic interactions with ammonium ions and by hydrogen bonds. Some specific structural features of crystals containing [UO2(L)2(NCS)]3? complexes, where L is the oxalate or malonate ion, are discussed.  相似文献   

9.
以Ni3[Ge2O5](OH)4为载体,氟钛酸铵为原料,采用水热辅助液相沉积法制备了纳米TiO2/ Ni3[Ge2O5](OH)4复合材料。通过X射线衍射(XRD)、拉曼光谱分析(RM)、场发射扫描电子显微镜(FE-SEM)、高分辨透射电镜(HTEM)、紫外-可见吸收光谱(UV-Vis)等表征手段对样品的物相组成、结构特性及微观形貌做了检测分析,并且探究了不同二氧化钛负载量对纳米TiO2/Ni3[Ge2O5](OH)4复合材料光降解亚甲基蓝能力的影响规律。结果表明,实验实现了纳米TiO2与Ni3[Ge2O5](OH)4的紧密复合与有效分散,TiO2为锐钛矿型结构,平均粒径20 nm。该复合材料能够有效抑制光生载流子的复合,改善材料的吸附性能,提高材料的光催化效率。当复合材料中TiO2与Ni3[Ge2O5](OH)4的摩尔比为3.1∶1时,材料对亚甲基蓝的光催化效率最高,90 min亚甲基蓝的光降解率为99.81%。  相似文献   

10.
Crystallography Reports - Crystals of new borate KTm[B4O6(OH)4] ? 3H2O (sp. gr. Р $$\bar {3}$$ 1m, a = 4.5472(7) Å, c = 12.151(3) Å) have been obtained under hydrothermal...  相似文献   

11.
在单晶X射线衍射实验的基础上,对孔道结构化合物V9P8-en的类质同象物V9(P,B)8-en的晶体结构和晶体化学进行了深入研究.结果表明,该化合物的晶体学数据为:P2(1)/n,a=1.43134(9)nm,b=1.01256(6)nm,c=1.83156(12)nm,β=90.280(2)°,V=2.6545(3)nm3,Z=2,R=0.0540,wR2=0.1551.结构中,沿着三个结晶轴方向发育复杂而规整的三维孔道,最大孔径达1.83nm(∥b轴),质子化乙二胺和水分子居于孔道中.硼部分替代四面体配位的磷,替代率为B8:P8=0.1838:7.8162;其中B与{P-OH}位P的替代量大于与[P-O]位P的替代量.相对于V9P8-en来说,V9(P,B)8-en的晶胞参数发生了变化,导致b轴增长(1.0150→1.0256nm)和c轴缩短(1.8374→1.8316nm),同时β角变小(90.39→90.278(2)°).二者的化学计量比也不同,体现在结构与孔容的关系、电荷平衡、满足亲水-疏水作用的结晶水的数量及有机模板分子的赋存状态等方面都有差异.  相似文献   

12.
The complex [Y(NO3)3(OH2)3]·(Me2-16-crown-5)·H2O has been prepared and its crystal and molecular structure determined using single crystal X-ray diffraction. The colorless crystals belong to the monoclinic space group P21/n with Z = 4. Lattice parameters are a = 10.420(1), b = 17.257(3), c = 14.646(2) Å, = 96.79(1)°, V = 2615.1(6) Å3. The yttrium(III) ion is nine-coordinate, bonded to three bidentate nitrate groups and three water molecules. The average Y–O(nitrate) and Y–O(water) distances are 2.42(3) and 2.33(1) Å, respectively. The average HO–H···O hydrogen bonded separation is 2.767Å.  相似文献   

13.
以硼酸和有机胺为原料在水溶液体系中合成了一种有机模板硼酸盐[C6N2H18]0.5[B5O6(OH)4](1a),通过X射线单晶衍射仪对其晶体结构进行了检测.此外,对其进行了元素分析、X射线粉末衍射、红外光谱、热重差热分析及固态荧光光谱等表征.结果表明,该化合物属单斜晶系,空间群为P21/n,晶胞参数为a=0.8593(2) nm,b=1.4015(4) nm,c=1.0293(3) nm,β=104.723(3)°,V=1.1989(6) nm3,Z=4.阴离子基团[B506 (OH)4]-通过强的氢键连接形成具有三种不同形状孔道的新颖三维超分子骨架结构.该化合物在波长为248 nm的激发光下,发射出最大发射波长为375 nm的紫外光.对化合物进行不同温度的热处理后,其荧光性质发生了明显的变化.  相似文献   

14.
为了探讨化学成份对VPO体系孔道结构化合物结构稳定性的影响,根据酸碱平衡原理进行了合成实验设计;利用V2O5、H3PO4、H3BO3等简单的无机前驱物、乙二胺作结构导向剂,水热法合成了孔道结构钒硼磷酸盐化合物(H3NCH2CH2NH3)2(H3NCH2CH2NH2)[VⅢ(H2O)2(VⅣO)8(OH)4(H(P,B)O4)4((P,B)O4)4(H2O)2]·3H2O(简称V9(P,B)8-en).典型的反应起始物摩尔比为n(V2O5):n(H3BO3):n(H3PO4):n(en):n(H2O)=0.89:3.50:3.50:3.60:265(pH值为6.5),在175℃、自生压力条件下恒温晶化6.5d(最终pH值为5.9).通过电子探针、粉末X射线衍射、红外吸收光谱、原子占位度修正等方法,对产物的化学成份、物相及其结构等进行了实验研究.证实V9(P,B)8-en为V9P8-en的类质同象化合物,不同晶粒中B与P的含量有差别,B与P之比为O.1:7.9~2.54:5.46(原子比),但恒有V:(P+B)≈9:8.表明通过合理设计和控制合成条件,可在保持V9P8-en基本结构不变的前提下通过同晶取代引入新的化学成份,并由此探讨成份与结构稳定性的关系.  相似文献   

15.
Compounds (CN3H6)2[UO2(OH)2(NCS)]NO3 (I) and β-Cs3[UO2(NCS)5] (II) are synthesized and studied by IR spectroscopy and single-crystal X-ray diffraction. I and II crystallize in the orthorhombic system. For I, a = 12.2015(13) Å, b = 7.3295(8) Å, c = 16.310(2) Å, space group Pnma, Z = 4, and R = 0.0327; for II, a = 21.7891(6) Å, b = 13.5120(3) Å, c = 6.8522(2) Å, space group Pnma, Z = 4, and R = 0.0268. In structure I, complex groups form infinite chains [UO2(OH)2(NCS)] n n? belonging to the AM 2 2 M 1 crystal chemical group of uranyl complexes (A = UO 2 2+ , M 2 = OH?, and M 1 = NCS?). The main structural elements of crystals II are mononuclear [UO2(NCS)5]3? groups belonging to the AM 5 1 group of uranyl complexes (A = UO 2 2+ and M 1 = NCS?). In I and II, uranium-containing complexes are connected with outer-sphere cations by electrostatic interactions, and in I a system of hydrogen bonds also contributes to their binding. Specific features of the packing of complex [UO2(NCS)5]3? groups in the structures of two modifications of Cs3[UO2(NCS)5] are discussed.  相似文献   

16.
The title complex was prepared by the addition of 15-crown-5, dissolved in acetone, to a solution of Y(NO3)3·nH2O in the same solvent. The crystal structure of this complex, determined by single-crystal X-ray diffraction using counter methods, was carried out on a crystal grown by slow evaporation of the reaction mixture at room temperature. [Y(NO3)3(OH2)3]·1.5(15-crown-5) Me2CO crystallizes in the acentric space group, P21, with unit cell dataa=15.900(5),b=16.530(6),c=11.821(5) Å,=92.12(3)°,D calc=1.53 g cm–3 forZ=4. Each unit cell consists of two dimers of the formula unit. One crown molecule bridges two [Y(NO3)3(OH2)3] units via hydrogen bonding with one water molecule of each. The two remaining water molecules per metal moiety form three hydrogen bonds to another 15-crown-5 molecule and one to an acetone molecule. The average bonding parameters in the nine-coordinate metal complexes are Y-O(NO3)=2.43(4) Å and Y-O(OH2)=2.34(5) Å.For Part 19 see Rogers, 1987.  相似文献   

17.
The crystal structures of [Cd(H2 Edta)(H2O)] · 2H2O (I) and [Mn(H2O)4][Mn(HEdta)(H2O)]2 · 4H2O (II) are studied by X-ray diffraction [R 1 = 0.0209 (0.0272), wR 2 = 0.0571 (0.0730) for 2551 (4025) reflections with I > 2σ(I) in I (II), respectively]. Structure I contains mononuclear [Cd(H2 Edta)(H2O)] complexes with the C 2 symmetry, and structure II contains centrosymmetric trinuclear [Mn(H2O)4][Mn(HEdta)(H2O)]2 complexes. In I and II, the protonated ligands are hexadentate (2N + 4O), and the water molecule increases the coordination number of the metal atom to seven. The acid protons participate in short intermolecular hydrogen bonds, which are symmetric in II and asymmetric in I.  相似文献   

18.
[(H3O)(C14H20O5)2][Me2NH2]2 [PMo12O40] · 2C14H20O5 1 was synthesized from benzo-15-crown-5 and H3PMo12O40·24H2O in N,N-dimethylformamide for the first time. 1 crystallizes in the monoclinic space group C2/c with a = 18.583(4), b = 25.510(5), c = 19.904(4) Å, = 94.66(3)° D c = 2.124 mg/m3 for Z = 4. Refinement based on 7358 observed reflections led to a R1(wR2) = 0.0378(0.0761). The complex cation, [(H3O)(C14H20O5)2]+, exhibits a sandwich structure by hydrogen-bonding in the mean distance of 2.955 Å. The anion, PMo12O40 3–, is a -Keggin structure.  相似文献   

19.
[HB(3,4,5-Me3pz)3]2Zn (1) and [H2B(3,4,5-Me3pz)2]Zn(-3,4,5-Me3pz)2Zn[H2B(3,4,5-Me3pz)2] (2) are present in equal amounts in a crystal in the triclinic space group, P-1 with a = 11.5924(11) Å, b = 12.7799(12) Å, c = 15.7317(14) Å = 107.905(2)° = 96.796(2)°, = 105.786(2)°, and Z = 1. The structure of 1 is a trigonally distorted octahedron and is very similar to the structure of [HB(3,5-Me2pz)3]2Zn showing that the introduction of the third methyl group on the pyrazolyl ring does not impact on structure. [H2B(pz)2]2Zn (3) is orthorhombic, Pca2(1) with a = 10.1473(3) Å, b = 11.1117(2) Å, c = 14.1831(5) Å, = = = 90° and Z = 4. The zinc(II) centers in both 2 and 3 are similar and have pseudotetrahedral structures.  相似文献   

20.
[M(saccharinato)2(H2O)4] (M = Cu2+, Ni2+, Co2+) react with nicotinamide to form mixed ligand complexes, [Cu(saccharinato)2(nicotinamide)(H2O)](H2O) (1) and [M(nicotinamide)2(H2O)4](saccharinate)2 (2: M = Ni2+; 3: M = Co2+), and their crystal structures have been determined by X-ray diffraction. In 1, the Cu2+ atom in an octahedral configuration is coordinated by two monodentate saccharinato ligands in the trans arrangement through the deprotonated ring nitrogens, by two bidentate nicotinamide ligands, one through the pyridyl ring nitrogen and the other through the amide oxygen, and by a water molecule, thus forming a nicotinamide-bridged one-dimensional extended structure. In the isomorphous complexes 2 and 3, the octahedral metal atom, which rides on a crystallographic center of symmetry, is coordinated by two monodentate nicotinamide ligands through the ring nitrogens and four water molecules to form a discrete [M(nicotinamide)2(H2O)4]2 + structural unit, which captures up and down two saccharinate ions, each through three hydrogen bonds: two hydrogen bonds between two water ligands and the ring N and the carbonyl O atoms and one between the amide N of the nicotinamide ligand and the carbonyl O.  相似文献   

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