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1.
Crystals of sodium zinc diiron(III) triphosphate, NaZnFe2(PO4)3, have been synthesized and structurally characterized by single‐crystal X‐ray diffraction. The compound features a new structural type built up from ZnO6 octahedra, FeO6 octahedra and FeO4 tetrahedra, linked together via the corners and edges of PO4 tetrahedra to form a three‐dimensional framework, with tunnels running along [100]. Within these tunnels, Na+ cations occupy a highly distorted cubic site.  相似文献   

2.
The title compound, Ca3ZnGeO2[Ge4O12] (tricalcium zinc germanium dioxide dodecaoxidotetragermanate), adopts a taikanite‐type structure. The tetrahedral [Ge4O12] chain geometry is very similar to that of the silicate chain of taikanite, i.e. BaSr2Mn3+2O2[Si4O12], while the major difference is found parallel to the c axis. In taikanite, Mn3+ octahedra form an infinite zigzag chain, whereas the title compound has a chain of distorted ZnO6 octahedra, which alternates with distorted GeO4 tetrahedra connected to each other via two common edges. Eightfold‐coordinated Ca2+ polyhedra and ZnO6 octahedra form a slab parallel to (001) which alternates with another slab containing the tetrahedrally coordinated Ge sites along the c axis.  相似文献   

3.
The title compound, potassium pentanickel hexaborophosphate tridecahydroxide, was synthesized under hydrothermal conditions from the NiCl2–K3PO4–B2O3–K2CO3–H2O system. The crystal structure was determined using single‐crystal X‐ray diffraction at 100 K. The KNi5[P6B6O23(OH)13] phase is cubic. For the three crystallographically distinct Ni centers, two occupy sites with 3 symmetry, while the third Ni and the K atom are located on sites. The structure is built from alternating borate and phosphate tetrahedra forming 12‐membered puckered rings with K+ ions at the centers. These rings are arranged as in cubic dense sphere packing. A novel feature of the new crystal structure is the presence of linear trimers of face‐sharing [NiO6] octahedra occupying the octahedral interstices of this sphere packing, and of single [NiO6] octahedra in the tetrahedral interstices. All oxygen corners of the Ni octahedra are linked to phosphate or borate tetrahedra of the 12‐membered rings to form a mixed anionic framework.  相似文献   

4.
The previously unknown crystal structure of magnesium perchlorate anhydrate, determined and refined from laboratory X‐ray powder diffraction data, represents a new structure type. The title compound was obtained by heating magnesium perchlorate hexahydrate at 523 K for 2 h under vacuum and it crystallizes in the monoclinic space group P21/c. The asymmetric unit contains one Mg (site symmetry on special position 2a), one Cl and four O sites (on general positions 4e). The structure consists of a three‐dimensional network resulting from the corner‐sharing of MgO6 octahedra and ClO4 tetrahedra. Each MgO6 octahedron share corners with six ClO4 tetrahedra. Each ClO4 tetrahedron shares corners with three MgO6 octahedra, with one O‐atom corner dangling. The ClO4 tetrahedra are oriented in such a way that one‐dimensional channels parallel to [100] are formed between the dangling O atoms.  相似文献   

5.
This study presents the first structural report of iranite, ideally CuPb10(CrO4)6(SiO4)2(OH)2 [copper decalead hexachromate bis(orthosilicate) dihydroxide], based on single‐crystal X‐ray diffraction data. Iranite is isomorphous with hemihedrite, with substitution of Cu for Zn and OH for F. The Cu atom is situated at the special position with site symmetry . The CrO4 and SiO4 tetrahedra and CuO4(OH)2 octahedra form layers that are parallel to (120) and are linked together by five symmetrically independent Pb2+ cations displaying a rather wide range of bond distances. The CuO4(OH)2 octahedra are corner‐linked to two CrO4 and two SiO4 groups, while two additional CrO4 groups are isolated. The mean Cr—O distances for the three nonequivalent CrO4 tetrahedra are all slightly shorter than the corresponding distances in hemihedrite, whereas the CuO4(OH)2 octahedron is more distorted than the ZnO4F2 octahedron in hemihedrite in terms of octahedral quadratic elongation.  相似文献   

6.
The crystal structure of the mixed oxide InGaO3(ZnO)4 has been determined from electron diffraction and single‐crystal X‐ray diffraction data. The compound crystallises in a hexagonal space group (P63/mmc; No. 194), deduced from convergent beam electron diffraction (CBED). Single crystals of InGaO3(ZnO)4 were grown from a K2MoO4 flux in sealed platinum tubes. Single crystal structure refinement from XRD data [a = 3.2850(2) Å; c = 32.906(3) Å; Z = 2; 4232 data, R1 = 0.0685] reveals a compound with oxygen anions forming a closest‐packed arrangement. Within this packing In3+ cations occupy octahedral interstices, forming layers of edge sharing octahedra. In between these layers are regions with composition [Zn4GaO5]+ forming a wurtzite type of structure. Inversions of the ZnO4 tetrahedra occurs (i) at the InO6 octahedral layer and (ii) halfway in the wurtzite type region, where the inversion boundary is built by Ga3+ in trigonal bipyramidal coordination with a long Ga–Oapical distance of 2.19(1) Å. The site occupation of Zn2+ and Ga3+, respectively, was confirmed by bond valence sum calculations. The compounds described here have the same structural charactistics as other known members with general formula ARO3(ZnO)m with m = integer.  相似文献   

7.
The crystal structure of the new complex vanadium oxide Na6Mg2(VO4)2(V2O7) was solved from X‐ray single‐crystal data. The structure contains VO4 tetrahedra and MgO6 octahedra, linked by corners and forming a complex three‐dimensional framework. A half of the VO4 tetrahedra are connected only to MgO6 octahedra, whereas the others are corner‐sharing, forming V2O7 pyrovanadate groups with statistically random orientations. One unique Mg atom is located at an inversion centre, while the other Mg atom, one unique V atom and five unique O atoms lie on mirror planes.  相似文献   

8.
Two new Keggin templated supramolecular compounds, [Zn2(H2biim)5(SiM12O40)] · 4H2O [M = W ( 1 ), Mo ( 2 )] (H2biim = 2, 2′‐biimidazole), were synthesized under hydrothermal conditions by using the ligand 2, 2′‐biimidazole. They were characterized by single‐crystal X‐ray diffraction, elemental analyses, IR and photoluminescence spectroscopy as well as cyclic voltammetry. The two isostructural compounds are constructed by two discrete supramolecular moieties: the inorganic chains consist of Keggin anions and metal‐organic chains constructed by [Zn2(H2biim)5]4+ subunits. In the dinuclear [Zn2(H2biim)5]4+ subunit, the H2biim ligands exhibit a dual role, chelating and linking. The metal‐organic chains further construct a 3D supramolecular framework with channels, in which the Keggin‐based inorganic chains are accommodated. The electrochemical behaviors of compounds 1 and 2 bulk‐modified carbon paste electrodes ( 1 ‐CPE, 2 ‐CPE) were studied.  相似文献   

9.
A new layered zinc phosphite with the formula (NH4)[{Zn(H2O)4}0.5Zn2(HPO3)3] has been synthesized under hydrothermal conditions. Its structure was determined by single‐crystal X‐ray diffraction. The compound crystallizes in the triclinic system, space group (No. 2), a = 7.2507(4), b = 9.7982(6), c = 10.2642(6) Å, α = 63.425(2), β = 87.165(2), γ = 72.999(3)°, V = 620.84(6) Å3, Z = 2. The connectivity of ZnO4 tetrahedra, HPO3 pseudo pyramids and ZnO2(H2O)4 octahedra results in macroanionic layers with 4.8 net.  相似文献   

10.
The title anion was synthesized by heating dimethylformamide (DMF) solution of the known Ni‐centered and Ni(CO)‐capped tin clusters [Ni@Sn9Ni(CO)]3?. The new anion represents the first example of face‐fused nine‐atom molecular clusters. The two clusters are identical elongated tricapped trigonal prisms of nido‐[Sn8Ni(CO)]6? with nickel at one of the capping positions. They are fused along a triangular face adjacent to a trigonal prismatic base and made of two Sn and one Ni atoms. The new anion is structurally characterized by single‐crystal X‐ray diffraction in the compound (K[222‐crypt])4[Sn14Ni(CO)]?DMF. Its presence in solution is corroborated by electrospray mass spectrometry.  相似文献   

11.
The crystal structures among M1–M2–(H)‐arsenites (M1 = Li+, Na+, K+, Rb+, Cs+, Ca2+, Sr2+, Ba2+, Cd2+, Pb2+; M2 = Mg2+, Mn2+,3+, Fe2+,3+, Co2+, Ni2+, Cu2+, Zn2+) are less investigated. Up to now, only the structure of Pb3Mn(AsO3)2(AsO2OH) was described. The crystal structure of hydrothermally synthesized Na4Cd7(AsO3)6 was solved from the single‐crystal X‐ray diffraction data. Its trigonal crystal structure [space group R$\bar{3}$ , a = 9.5229(13), c = 19.258(4) Å, γ = 120°, V = 1512.5(5) Å3, Z = 3] represents a new structure type. The As atoms are arranged in monomeric (AsO3)3– units. The surroundings of the two crystallographically unique sodium atoms show trigonal antiprismatic coordination, and two mixed Cd/Na sites are remarkably unequal showing tetrahedral and octahedral coordinations. Despite the 3D connection of the AsO3 pyramids, (Cd,Na)Ox polyhedra and NaO6 antiprisms, a layer‐like arrangement of the Na atoms positioned in the hexagonal channels formed by CdO4 deformed tetrahedra and AsO3 pyramids in z = 0, 1/3, 2/3 is to be mentioned. These pseudo layers are interconnected to the 3D network by (Cd,Na)O6 octahedra. Raman spectra confirmed the presence of isolated AsO3 pyramids.  相似文献   

12.
IntroductionInthelastfewyearsthesearchfornewmaterialswithmicroporousandzeolite analogoussystemshasprimarilyfocusedonaluminumphosphatesandaluminosilicatecom poundssubstitutedwithavarietyofatoms .1 3 Cobalt sub stitutedaluminophosphatesaresystematicallystudiedmainlyduetotheirpotentialuseassolid acidcatalysts .Insuchmaterials ,theBr nstedacidsiteisgeneratedbyeachsubstitutionofAl(III)byCo(II)inwhichaprotonisneededtobalancethecharge .4 7Tofindnewtypeofze oliticmaterials ,theborophosphatemateri…  相似文献   

13.
New compounds, K10M2+ Mo7O27 (M2+ = Mg, Mn, Co), have been synthesized and characterized. The compounds have an original structure, as established for the first two phases (orthorhombic, space group Pnm21, Z = 2, a = 18353 and 18.402, b = 7.889 and 7.931, c = 10.566 and 10.604 å, R = 0.0345 and 0.0609, respectively). A specific feature of the structure is isolated clusters consisting of face-sharing MoO6 and M2+O6 octahedra, each of the latter having six MoO4 tetrahedra attached to it by vertices. The general pseudohexagonal motif of the structure of the phases is similar to that of glaserites.  相似文献   

14.
Single crystals of the high‐temperature modification of zinc catena‐polyphosphate, β‐Zn(PO3)2, were grown from a melt and quenched from 1093 K to room temperature. The structure was solved from single‐crystal X‐ray diffraction data and is built of corrugated (PO3) polyphosphate chains, which extend along the c direction with an eight‐tetrahedra repeat. Slightly distorted [ZnO4] tetrahedra link the polyphos­phate chains into a three‐dimensional network.  相似文献   

15.
The crystal structures of hydro­thermally synthesized potassium scandium hydrogen arsenate(V), KSc(HAsO4)2, (I), and rubidium scandium diarsenate(V), RbScAs2O7, (II), were determined from single‐crystal X‐ray diffraction data collected at room temperature. Compound (I) represents a new microporous structure type, designated MCV‐3, which is characterized by a three‐dimensional framework of corner‐sharing alternating ScO6 octahedra and HAsO4 tetrahedra. Intersecting tunnels parallel to [101] and [110] host eight‐coordinate K atoms. There is one hydrogen bond of medium strength [O⋯O = 2.7153 (18) Å]. Compound (II) is the first reported diarsenate with a KAlP2O7‐type structure and is isotypic with at least 27 AIMIII diphosphates. The average Sc—O bond lengths in (I) and (II) are 2.09 (2) and 2.09 (3) Å, respectively. The K and Sc atoms in (I) lie on an inversion centre and a twofold axis, respectively. All atoms in (II) are in general positions.  相似文献   

16.
A new inorganic‐organic hybrid zinc phosphate with the formula Zn2(4, 4'‐bipy)(HPO4)2 (4, 4'‐bipy = 4, 4'‐bipyridine) has been synthesized under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, FTIR, ICP analysis, elemental analysis, SEM, powder X‐ray diffraction, thermogravimetric analysis and its fluorescent spectrum. The compound crystallizes in the monoclinic system, space group P21/c (No.14), a = 10.4479(7), b = 8.1694(5), c = 8.9643(5) Å, β = 97.907(2), V = 757.86(8) Å3, Z = 2. The structure consists of ZnO3N and HPO4 tetrahedra by corner‐sharing to generate neutral 4.82‐net sheets, which are pillared through 4, 4'‐bipy ligands to form a 3‐D hybrid framework.  相似文献   

17.
Dizinc selenium dichloride trioxide, β‐Zn2(SeO3)Cl2, a monoclinic polymorph of the orthorhombic mineral sophiite, has a structure built of distorted ZnO4Cl2 octahedra, ZnO2Cl2 tetrahedra and SeO3E tetrahedra (E being the 4s2 lone pair of the SeIV ion), joined through shared edges and corners to form charge‐neutral layers. The Cl atoms and the Se lone pairs protrude from each layer towards adjacent layers. The main structural difference between the mineral and synthetic polymorphs lies in the packing of the layers.  相似文献   

18.
A new metal borophosphate PbII4{Co2[B(OH)2P2O8](PO4)2}Cl ( 1 ), containing both Pb2+ cations and Cl anions, was hydrothermally synthesized and characterized by powder X‐ray diffraction, ICP, TG/DTA, and FTIR spectroscopic analyses. The crystal structure determination from single‐crystal X‐ray diffraction reveals that compound 1 crystallizes in the trigonal space group R c (No. 167), a = 9.7513(7) Å, c = 91.060(13) Å, V = 7498.7(13) Å3 and Z = 18. Its structure features a new cobalt borophosphate layer {Co2[B(OH)2P2O8](PO4)2}7– built up from CoO5 square pyramids, [B(OH)2P2O8]5– borophosphate trimers and PO4 tetrahedra. Extra‐framework Pb2+ and Cl ions are located at the vacancy of layers to achieve the charge neutrality of the framework. Magnetic measurements indicate that antiferromagnetic interactions exist between Co2+ ions with a negative Weiss constant of –20.3 K.  相似文献   

19.
The synthesis of a new potassium titanosilicate, K4Ti2Si6O18 (Ti-AV-11), possessing the crystal structure of potassium stannosilicate AV-11, has been reported. The unit cell of this material is trigonal, space group R3 (no. 146), Z=3, a=10.012, c=14.8413 Å, γ=120°, V=1289 Å3. The structure of AV-11 is built up of MO6 (M=Sn, Ti) octahedra and SiO4 tetrahedra by sharing corners. The SiO4 tetrahedra form helix chains, periodically repeating every six tetrahedra. These chains extend along the [001] direction and are linked by isolated MO6 octahedra, thus producing a mixed octahedral-tetrahedral oxide framework. AV-11 materials have been further characterized by bulk chemical analysis, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), 29Si and 119Sn magic-angle spinning (MAS) NMR spectroscopy.  相似文献   

20.
Dodecameric (Sn12) and hexameric topologies dominate monoalkyltin–oxo cluster chemistry. Their condensation, triggered by radiation exposure, recently produced unprecedented patterning performance in EUV lithography. A new cluster topology was crystallized from industrial n ‐BuSnOOH, and additional characterization techniques indicate other clusters are present. Single‐crystal X‐ray analysis reveals a β‐Keggin cluster, which is known but less common than other Keggin isomers in polyoxometalate and polyoxocation chemistry. The structure is formulated [NaO4(BuSn)12(OH)3(O)9(OCH3)12(Sn(H2O)2)] (β‐NaSn13). SAXS, NMR, and ESI MS differentiate β‐NaSn13, Sn12, and other clusters present in crude “n ‐BuSnOOH” and highlight the role of Na as a template for alkyltin Keggin clusters. Unlike other alkyltin clusters that are cationic, β‐NaSn13 is neutral. Consequently, it stands as a unique model system, absent of counterions, to study the transformation of clusters to films and nanopatterns.  相似文献   

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