共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
3.
Tetradecacobalt(II)‐Containing 36‐Niobate [Co14(OH)16(H2O)8Nb36O106]20− and Its Photocatalytic H2 Evolution Activity
下载免费PDF全文
![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Prof. Jingyang Niu Fang Li Dr. Junwei Zhao Pengtao Ma Dr. Dongdi Zhang Dr. Bassem Bassil Prof. Ulrich Kortz Prof. Jingping Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9852-9857
A gigantic Co14‐containing 36‐niobate, Na12K8[Co14(OH)16(H2O)8Nb36O106] ? 71H2O ( 1 ), has been prepared by the hydrothermal method and structurally characterized. Polyanion [Co14(OH)16(H2O)8Nb36O106]20? ( 1 a ) comprises a central Co7 core, surrounded by another seven isolated Co2+ ions and six Lindqvist‐type (Nb6O19) hexaniobate fragments. This is the first example of a high‐nuclear cobalt‐cluster‐containing polyoxoniobate. The photocatalytic H2 evolution activity of Pt‐loaded 1 was observed in methanol solution under irradiation using a 300 W Xe lamp. 相似文献
4.
5.
Elisaveta V. Cherkasova Eugenia V. Peresypkina Alexander V. Virovets Nina V. Podberezskaya Tatyana G. Cherkasova 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):m195-m198
The title compound, [Er(C6H11NO)8][Cr(NCS)6], is a new structure type for [Ln(ɛ‐caprolactam)8][Cr(NCS)6], where Ln is a lanthanide. There are two independent cations and two independent anions in the asymmetric unit. The Er atom is in a distorted square‐antiprismatic environment of eight O atoms of the organic ligands; Er—O bond distances are in the range 2.29–2.44 Å. The coordination environment of the Cr atom is a slightly distorted octahedron; Cr—N bond distances vary from 1.99 to 2.01 Å. The mutual packing of the cations and the anions follows a distorted NaCl motif. One cation has the Er atom on a twofold axis and one of the anions has the Cr atom on a twofold axis. 相似文献
6.
Hong Ryol Suh Hyung Sock Suh Sock Sung Yun Eun Kwang Lee Sung Kwon Kang 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):m202-m203
In the title compound, [Y(C6H3N2O5)3(H2O)3], the Y atom is nine‐coordinate with a slightly distorted tricapped trigonal prismatic coordination geometry. The YIII ion is coordinated to three bidentate 2,6‐dinitrophenolate ligands and three water molecules. The Y—O bond distances are in the range 2.217 (3)–2.754 (4) Å, with the Y—O distances from the nitro groups being longer than those from the water molecules and the phenol groups. The coordinated NO2 groups are almost coplanar with the benzene rings. 相似文献
7.
Iaki Muga Pablo Vitoria Antonio Luque Juan M. Gutirrez‐Zorrilla Carmen Guzmn‐Miralles Pascual Romn 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):m81-m83
The title compound, [Ni2(C2O4)(C4H13N3)2(H2O)2](PF6)2·‐2H2O, contains a dinuclear oxalato‐bridged nickel(II) complex cation. The structure determination reveals the presence of a centrosymmetric binuclear complex where the oxalate ligand is coordinated in a bis‐bidentate mode to the Ni atoms. The distorted octahedral environment of each Ni atom is completed by the three N atoms of the diethylenetriamine ligand in a fac arrangement and by one O atom from a water molecule. PF6? acts as counter‐anion. A two‐dimensional network of hydrogen bonds links the cations and anions and stabilizes the structure. 相似文献
8.
9.
Jan Moncol Klaudia Jomova Lubomir Zelenicky Tadeusz Lis Marian Valko 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(9):m318-m320
The title compound, [Cu4(C7H4ClO2)4(C6H6NO)4], consists of isolated tetranuclear clusters, where the Cu2+ cations are five‐ and sixfold coordinated by O atoms from the 4‐chlorobenzoate anions and by pyridine N and methanolate O atoms from bidentate 2‐pyridylmethanolate ligands. While three Cu atoms are six‐coordinated by an NO5 donor set forming distorted octahedra, the fourth Cu atom is five‐coordinated by an NO4 donor set forming a distorted tetragonal–pyramidal coordination around the Cu atom. The nucleus is a deformed cubane‐like Cu4O4 structure, with Cu...Cu distances in the range 3.0266 (11)–3.5144 (13) Å. 相似文献
10.
Hoong‐Kun Fun S. Kannan Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m368-m370
In the title compound, [UO2(C15H11O2)2(C14H14OS)], the UVI atom is coordinated by seven O atoms in a distorted pentagonal–bipyramidal geometry. Both diphenylpropane‐1,3‐dionate systems are nearly planar. The sulfoxide moiety is in a distorted tetrahedral geometry, while its two aromatic rings are nearly orthogonal to one another. The crystal packing is stabilized by two bifurcated hydrogen‐bonding interactions involving both uranyl O atoms. 相似文献
11.
Li‐Qin Xiong Chuan‐Min Qi 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):m10-m12
The title compound, [La2(C8H3NO6)2(C8H4NO6)2(H2O)6]·2H2O, consists of dimeric units related by an inversion center. The two LaIII atoms are linked by two bridging bidentate carboxylate groups and two monodentate carboxylate groups. Each LaIII atom is nine‐coordinated by six O atoms from five different carboxylate groups and three from water molecules. Hydrogen bonds between the water molecules and between the solvent water and a carboxylate O atom are observed in the structure. In the crystal packing, there are slipped π–π stacking interactions between the parallel benzene rings. Both hydrogen‐bonding and π–π interactions combine to stabilize the three‐dimensional supramolecular network. 相似文献
12.
Marijana ?akovi Zora Popovi 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):m557-m559
In the title compound, [Hg(NO3)(C6H6N2O)2]NO3, the HgII atom is five‐coordinate. The distorted square‐pyramidal mercury(II) coordination environment is achieved by two N,O‐bidentate picolinamide ligands, with one O‐monodentate nitrate ion in the apical position. A seven‐coordinate extended coordination environment is completed by two additional weak Hg...O interactions, one from the coordinated nitrate ion and one from the other nitrate ion, to give seven‐coordination. The molecules are linked into a two‐dimensional network by N—H...O hydrogen bonds. 相似文献
13.
Mao‐Lin Hu Peng Gao Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):m323-m324
The Cd atom in the polymeric title compound, [Cd(C14H8O5)(H2O)]n, is linked to four carboxyl O atoms and a water molecule in a five‐coordinate coordination polyhedron that is midway between a square pyramid and a trigonal bipyramid. The Cd atom and the water molecules both lie on the same twofold axis and the central O atom of the 4,4′‐oxydibenzoate moiety lies on another twofold axis. Covalent Cd—O bonds lead to the formation of a layer architecture perpendicular to the twofold axis, the layers being held together by hydrogen bonds in the third direction. 相似文献
14.
Leyla Tatar Gülsün Gkaac Diner Ülkü 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):668-669
The title compound, [Cu(C6H2Br3O)2(NH3)2], a monomeric centrosymmetric CuII complex, crystallizes in the monoclinic system. The CuO2N2 coordination sphere is trans planar, [Cu—O 1.943 (5) Å and Cu—N 1.977 (6) Å], with the fifth and sixth coordination sites occupied by Br atoms from the phenoxide ions [Cu—Br 3.129 (1) Å], resulting in an elongated distorted octahedral structure for the CuO2N2Br2 coordination. Each of the NH3 groups forms two hydrogen bonds with the Br and O atoms of the CuO2N2Br2 moiety of a neighbouring molecule. This arrangement constitutes a one‐dimensional chain along the x axis of the unit cell. 相似文献
15.
Nathalie Guillou Carine Livage Jrme Marrot Grard Frey 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1427-1428
The hydrothermal reaction of cobalt(II) chloride with trimesate (3,5‐dicarboxybenzoate) ions in aqueous solution gives the novel title complex, [Co(C9H5O6)2(H2O)4]. The CoII ion lies on an inversion centre and is octahedrally coordinated to two trimesate anions and four water molecules. Hydrogen bonds ensure the three‐dimensional architecture of the structure. 相似文献
16.
Cornelis Lensink Graeme J. Gainsford Neville I. Baxter 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):366-367
The title compound, [Ti(CF3O3S)2(C14H15NO2S)(C4H8O)], contains a unique ligand system in which the Ti ion is bound to the N and O atoms of a 2‐p‐toluenesulfonamide ligand, which is linked by an ethyl group to a coordinated cyclopentadiene moiety. The distorted octahedral geometry about the Ti ion is completed by two trifluoromethanesulfonate ligands and a tetrahydrofuran molecule. Comparison with related compounds shows that both the Ti—N and Ti—O bonds of the sulfonamide, although longer than normal values, indicate significant bonding interactions. 相似文献
17.
Lifang Chen Juncheng Hu Dr. Sib Sankar Mal Dr. Ulrich Kortz Prof. Helge Jaensch Dr. Georges Mathys Dr. Ryan M. Richards Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(30):7490-7497
The selective oxidation of alkanes as a green process remains a challenging task because partial oxidation is easier to achieve with sacrificial oxidants, such as hydrogen peroxide, alkyl hydroperoxides or iodosylbenzene, than with molecular oxygen or air. Here, we report on a heterogeneous catalyst for n‐hexadecane oxidation comprised of the wheel shaped Cu20‐polyoxotungstate [Cu20Cl(OH)24(H2O)12(P8W48O184)]25? anchored on 3‐aminopropyltriethoxysilane (apts)‐modified SBA‐15. The catalysts were characterized by powder X‐ray diffraction (XRD), N2‐adsorption measurements and Fourier transform infrared reflectance (FT‐IR) spectroscopy. The heterogeneous Cu20‐polyanion system catalyzed the solvent‐free aerobic oxidation of n‐hexadecane to alcohols and ketones by using air as the oxidant under ambient conditions. The catalyst exhibits an exceptionally high turn over frequency (TOF) of 20 000 h?1 at 150 °C and is resistant to poisoning by CS2. Moreover, it can be easily recovered and reused by filtration without loss of its catalytic activity. Possible homogeneous contributions also have been examined and eliminated. Thus, this system can use air as oxidant, which, in combination with its good overall performance and poison tolerance, raises the prospect of this type of heterogeneous catalyst for practical applications. 相似文献
18.
Methyl (22E)‐3‐oxochola‐1,4,22‐trien‐24‐oate ( 4 ; C25H34O3) is a naturally occurring steroid with unknown configuration at C(20). Starting from the (20S)‐3‐oxo‐23,24‐dinorchol‐4‐en‐22‐al ( 1a ), we prepared both diastereoisomeric methyl esters 4a and 4b by a three‐step procedure (Scheme). In the case of 4b , the initial epimerization of aldehyde 1a was followed by completion of the sequence and then separation via fractional crystallization to afford pure (20R)‐methyl ester 4a and its (20S)‐diastereomer 4b . Only the analytical data of the (20S)‐compound 4b were in good agreement with those reported for the natural product. 相似文献
19.
Mirka Bergamo Tiziana Beringhelli Giuseppe D'Alfonso Pierluigi Mercandelli Massimo Moret Angelo Sironi 《Angewandte Chemie (International ed. in English)》1998,37(15):2128-2131
The first five-membered rings of metal atoms connected by M–M or M-H-M bonds only have been obtained by a Re2+Re3 condensation in which a polyhydride acts as a bridging bidentate ligand toward a coordinatively unsaturated fragment (see scheme below). In spite of the octahedral coordination of the Re centers, the Re5 rings display conformations (twisted and envelope) comparable with those observed for organic five-membered rings of tetrahedral carbon atoms. 相似文献
20.
Jie Chen Ning‐Hai Hu Jie Zhan Yue‐Sheng Li 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(7):m337-m338
A new polynuclear titanium(IV) complex, dichlorodeca‐μ2‐oxo‐hexakis(pentamethylcyclopentadienyl)hexatitanium(IV), [Ti6(C10H15)6Cl2O10], has been synthesized by hydrolysis of a titanium complex bearing an N‐(2‐hydroxy‐3,5‐dimethylbenzyl)diethanolamine Mannich ligand. The molecule has two O‐bridged Ti3O3 rings linked to two similar rings through a tetrahedrally O‐coordinated Ti atom. All Ti atoms except the central one are coordinated to pentamethylcyclopentadienyl (Cp*) ligands. The Cp* ligands are arranged with approximate symmetry with respect to the Ti/O/Cl core. 相似文献