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1.  Zirconium(IV) dilanthanum(III) penta­sulfide 
Zirconium(IV) dilanthanum(III) penta­sulfide, ZrLa2S5, crystallizes with four formula units in the space group Pnma in the U3S5 structure type. The asymmetric unit comprises one Zr, one La and four S atoms. The Zr and three S atoms are situated on mirror planes. The structure consists of LaS8 face-sharing bicapped distorted trigonal prisms and ZrS7 edge-sharing monocapped octa­hedra.
doi:10.1107/S1600536811045193
PMCID: PMC3238577  PMID: 22199468
2.  An ortho­rhom­bic polymorph of the ultraphosphate YP5O14  
Single crystals of yttrium penta­phosphate(V), YP5O14, were obtained by solid-state reaction. The ortho­rhom­bic title compound belongs to the family of ultraphosphates and is the second polymorph of this composition. It is isotypic with its Ho and Er analogues. The structure contains two bridging Q 2-type PO4 tetra­hedra and one branching Q 3-type PO4 tetra­hedron, leading to infinite ultraphosphate ribbons running along the a axis. The coordination polyhedron around the Y3+ cation may be described as distorted bicapped trigonal-prismatic. The YO8 polyhedra are isolated from each other. They are linked by corner-sharing to the O atoms of six Q 2-type and of two Q 3-type PO4 tetra­hedra into a three-dimensional framework.
doi:10.1107/S1600536809007193
PMCID: PMC2968816  PMID: 21582306
3.  NaSr(AsO4)(H2O)9: the (Sr,As) analogue of nabaphite and nastrophite 
The crystal structure of the title compound, sodium strontium orthoarsenate(V) nona­hydrate, is isotypic with NaSr(PO4)(H2O)9 and the minerals nabaphite [NaBa(PO4)(H2O)9] and nastrophite [Na(Sr,Ba)(PO4)(H2O)9]. The Na and Sr atoms are located on threefold rotation axes and are in the centres of slightly distorted Na(H2O)6 octa­hedra and Sr(H2O)9 tricapped trigonal prisms, respectively. A framework structure is established via edge-sharing of these polyhedra. Disordered AsO4 tetra­hedra (with threefold symmetry) are situated in the inter­stitial space of the framework. Although reasonable H-atom positions of the water mol­ecules were not established, close O⋯O contacts between the disordered AsO4 tetra­hedra and the water mol­ecules suggest strong O—H⋯O hydrogen bonding.
doi:10.1107/S1600536809040355
PMCID: PMC2971340  PMID: 21578034
4.  KNb1.75V0.25PS10  
The title compound, potassium diniobium vanadium phospho­rus deca­sulfide, KNb1.75V0.25PS10, was obtained by reaction of the elements with a eutectic mixture of KCl/LiCl. It is isostructural with the quaternary KNb2PS10, but the Nb sites are occupied by statistically disordered Nb (87.5%) and V (12.5%) atoms. The structure is composed of anionic ∞ 1[M 2PS10]− chains (M = Nb/V) separated from each other by K+ ions. The chain is composed of [MS8] distorted bicapped trigonal prisms and [PS4] tetra­hedra. There are no inter­chain bonding inter­actions. The crystal used for the X-ray analysis was a racemic twin.
doi:10.1107/S1600536811004430
PMCID: PMC3051977  PMID: 21522232
5.  Barium dierbium(III) tetra­sulfide 
Barium dierbium(III) tetra­sulfide, BaEr2S4, crystallizes with four formula units in the ortho­rhom­bic space group Pnma in the CaFe2O4 structure type. The asymmetric unit contains two Er, one Ba, and four S atoms, each with .m. site symmetry. The structure consists of channels formed by corner- and edge-sharing ErS6 octa­hedra in which Ba atoms reside. The resultant coordination of Ba is that of a bicapped trigonal prism.
doi:10.1107/S1600536813003541
PMCID: PMC3588518  PMID: 23476480
6.  Hafnium germanium telluride 
The title hafnium germanium telluride, HfGeTe4, has been synthesized by the use of a halide flux and structurally characterized by X-ray diffraction. HfGeTe4 is isostructural with stoichiometric ZrGeTe4 and the Hf site in this compound is also fully occupied. The crystal structure of HfGeTe4 adopts a two-dimensional layered structure, each layer being composed of two unique one-dimensional chains of face-sharing Hf-centered bicapped trigonal prisms and corner-sharing Ge-centered tetra­hedra. These layers stack on top of each other to complete the three-dimensional structure with undulating van der Waals gaps.
doi:10.1107/S1600536808011380
PMCID: PMC2961149  PMID: 21202163
7.  Poly[[aqua­tris­(μ4-benzene-1,2-dicarboxyl­ato)dilanthanum(III)] hemihydrate] 
The asymmetric unit of the title coordination polymer, {[La2(C8H4O4)3(H2O)]·0.5H2O}n, contains two independent LaIII atoms, one of which is surrounded by eight carboxyl­ate-O atoms from six benzene-1,2-dicarboxyl­ate (BDC) anions in a bicapped trigonal–prismatic geometry. The other LaIII atom is nine-coordinated in a tricapped trigonal–prismatic geometry, formed by eight carboxyl­ate-O atoms from six BDC anions and a coordinated water mol­ecule. The BDC anions bridge the LaIII atoms, forming a two-dimensional polymeric complex parallel to (001). The crystal structure contains weak O—H⋯O and non-classical C—H⋯O hydrogen bonds. A C—H⋯π inter­action is also present in the crystal structure. The uncoordinated water molecule shows half-occupation.
doi:10.1107/S1600536811036282
PMCID: PMC3201334  PMID: 22064614
8.  Dy8SnS13.61O0.39 from single-crystal data 
Crystals of the title dysprosium tin sulfide oxide, Dy8SnS13S1−xOx [x = 0.39 (4)], were obtained unintentionally from the Dy–Sn–S system. A statistical mixture of sulfur and oxygen was assumed for one position in the structure. S and O atoms surround each of the eight symmetrically non-equivalent dysprosium atoms. The Sn atoms are located in tetra­hedral surroundings of sulfur atoms. Trigonal prisms and tetra­hedra are connected to each other by their edges. All atoms are situated in mirror planes.
doi:10.1107/S1600536807063416
PMCID: PMC2914880  PMID: 21200452
9.  Thallium(I) copper(I) thorium(IV) tris­elenide, TlCuThSe3  
Thallium(I) copper(I) thorium(IV) tris­elenide, TlCuThSe3, crystallizes with four formula units in the space group Cmcm in the KCuZrS3 structure type. There is one crystallographic­ally independent Th, Tl, and Cu atom at a site of symmetry 2/m.., m2m, and m2m, respectively. There are two crystallographically independent Se atoms at sites of symmetry m.. and m2m. The structure consists of sheets of edge-sharing ThSe6 octa­hedra and CuSe4 tetra­hedra stacked parallel to the (010) face, separated by layers filled with chains of Tl running parallel to [100]. Each Tl is coordinated by a trigonal prism of Se atoms.
doi:10.1107/S1600536812026669
PMCID: PMC3393138  PMID: 22807695
10.  Zn1.86Cd0.14(OH)VO4  
The title compound, dizinc cadmium hydroxide tetraoxido­vanadate, Zn1.86Cd0.14(OH)VO4, was prepared under low-temperature hydro­thermal conditions. It is isostructural with Zn2(OH)VO4 and Cu2(OH)VO4. In the crystal structure, chains of edge-sharing [ZnO6] octahedra are inter­connected by VO4 tetra­hedra (site symmetries of both V atoms and their coordination polyhedra are .m.) to form a three-dimensional [Zn(OH)VO4]2− framework with channels occupied by Zn and Zn/Cd cations adopting trigonal–bipyramidal and distorted octa­hedral coordinations, respectively. Zn1.86Cd0.14(OH)VO4 is topologically related to adamite-type phases, and descloizite- and tsumcorite-type structures.
doi:10.1107/S1600536810044806
PMCID: PMC3011449  PMID: 21589202
11.  Poly[diaqua­tris(μ4-isophthalato)dilanthanum(III)] 
In the title coordination polymer, [La2(C8H4O4)3(H2O)2]n, there are two independent LaIII atoms which are coordinated differently in slightly distorted penta­gonal-bipyramidal and slightly disorted bicapped trigonal-prismatic environments. The LaIII ions are bridged by μ4-isophthalate ligands, forming two-dimensional layers. In the crystal structure, these layers are connected by inter­molecular O—H⋯O hydrogen bonds into a three-dimensional network.
doi:10.1107/S1600536809054543
PMCID: PMC2979801  PMID: 21579693
12.  The mixed-metal tris­(di­sulfide) thio­phosphate, KNb1.77Ta0.23PS10  
The title compound catena-poly[potassium [tri-μ-disulfido-μ-tetra­thiophos­pha­to-di[niobate(IV)/tantalate(IV)(0.885/0.115)]]], has been obtained through the reaction of the elements with KCl. The title compound is isostructural with KNb2PS10, with the Nb sites occupied by statistically disordered Nb (88.5%) and Ta (11.5%) atoms. The structure is composed of anionic ∞ 1[M 2PS10]− chains along [100] (M = Nb/Ta) and K+ ions. This chain is built up from distorted bicapped trigonal prisms [MS8] and [PS4] tetra­hedra. There are no inter­chain bonding inter­actions, except for electrostatic and van der Waals forces. The S2 2− and S2− anionic species and the M 4+–M 4+ pair [M—M = 2.8939 (3) Å] are observed. The classical charge balance is represented by [K+][M 4+]2[PS4 3−][S2 2−]3.
doi:10.1107/S1600536814000592
PMCID: PMC3998242  PMID: 24764804
13.  Dipraseodymium(III) pyroborate molybdate(VI), Pr2(B2O5)(MoO4) 
Single crystals of triclinic Pr2(B2O5)(MoO4) were prepared from an incongruently melting flux in the system Pr2O3–MoO3–B2O3 in a platinum crucible in an atmosphere of air. In the crystal structure, distorted edge-sharing [PrO8] square anti­prisms form a three-dimensional framework. These are further linked by isolated [MoO4] tetra­hedra and isolated pyroborate groups [B2O5], the latter consisting of two independent trigonal [BO3] groups sharing one O atom. The [MoO4] tetra­hedra and the [B2O5] groups are arranged in alternating layers parallel to the ab plane.
doi:10.1107/S1600536808010386
PMCID: PMC2961550  PMID: 21202431
14.  The aluminoarsenate K1.8Sr0.6Al3(AsO4)4  
The title compound, potassium strontium trialuminium tetra­arsenate, was prepared by solid-state reaction. The structure consists of AlO6 octa­hedra (site symmetries 2.. and 2/m) and two AsO4 tetra­hedra (.2. and m..) sharing corners and edges to form a two-dimensional structure parallel to (010). The cations are occupationally disordered and are located in the interlayer space. For both types of cations, distorted coordination polyhedra are observed.
doi:10.1107/S1600536812014304
PMCID: PMC3344283  PMID: 22590049
15.  Redetermination of the low-temperature polymorph of Li2MnSiO4 from single-crystal X-ray data 
Crystals of dilithium manganese(II) silicate were grown under high-temperature hydro­thermal conditions in the system LiOH—MnO2—SiO2. The title compound crystallizes in the βII-Li3PO4 structure type. The coordination polyhedra of all cations are slightly distorted tetra­hedra (m symmetry for MnO4 and SiO4), which are linked by corner-sharing to each other. The vertices of the tetra­hedra point to the same direction perpendicular to the distorted hexa­gonal close-packed (hcp) array of O atoms within which half of the tetra­hedral voids are occupied by cations. In comparison with the previous refinement from powder X-ray data [Dominko et al. (2006 ▶). Electrochem. Commun. 8, 217–222], the present reinvestigation from single-crystal X-ray data allows a more precise determination of the distribution of the Li+ and Mn2+ cations, giving a perfectly site-ordered structure model for both Li+ and Mn2+.
doi:10.1107/S1600536812035040
PMCID: PMC3435565  PMID: 22969438
16.  Rietveld refinement of Y2GeO5  
Y2GeO5 (yttrium germanium penta­oxide) was synthesized by solid-state reaction at 1443 K. The arrangement, which has monoclinic symmetry, is isostructural with Dy2GeO5 and presents two independent sites for the Y atoms. Around these atoms there are distorted six-coordinated YO6 octa­hedra and seven-coordinated YO7 penta­gonal bipyramids. The YO7 polyhedra are linked together, sharing their edges along a surface parallel to ab, forming a sheet. Each of these parallel sheets is inter­connected by means of GeO4 tetra­hedra, sharing an edge (or vertex) on one side and a vertex (or edge) on the other adjacent side. Parallel sheets of YO7 polyhedra are also inter­connected by undulating chains of YO6 octa­hedra along the c axis. These octa­hedra are joined together, sharing a common edge, to form the chain and share edges with the YO7 polyhedra of the sheets.
doi:10.1107/S1600536809026579
PMCID: PMC2977227  PMID: 21583296
17.  Ba2Sb4GeS10  
The title quaternary compound, dibarium tetra­anti­mony germanium deca­sulfide, Ba2Sb4GeS10, crystallizes in a novel three-dimensional ∞ 3[Sb4GeS10]4− network structure, which is composed of triangular pyramidal SbS3 (site symmetry m..), distorted SbS5 (m..) polyhedra and regular GeS4 (-4..) tetra­hedra. The SbS3 and SbS5 units are connected with each other through corner- and edge-sharing, forming a Sb4S10 layer in the ab plane. The GeS4 tetra­hedra further bridge two neighbouring Sb4S10 layers, forming a three-dimensional ∞ 3[Sb4GeS10]4− network. The Ba2+ cation (..2) is located between two Sb4S10 layers and is coordinated by ten S atoms with Ba—S bond lengths in the range 3.2505 (9)–3.4121 (2) Å.
doi:10.1107/S1600536813007988
PMCID: PMC3647782  PMID: 23723748
18.  Li0.5Al0.5Mg2(MoO4)3  
The title compound, lithium/aluminium dimagnesium tetra­kis­[orthomolybdate(VI)], was prepared by a solid-state reaction route. The crystal structure is built up from MgO6 octa­hedra and MoO4 tetra­hedra sharing corners and edges, forming two types of chains running along [100]. These chains are linked into layers parallel to (010) and finally linked by MoO4 tetra­hedra into a three-dimensional framework structure with channels parallel to [001] in which lithium and aluminium cations equally occupy the same position within a distorted trigonal–bipyramidal coordination environment. The title structure is isotypic with LiMgIn(MoO4)3, with the In site becoming an Mg site and the fully occupied Li site a statistically occupied Li/Al site in the title structure.
doi:10.1107/S1600536813022046
PMCID: PMC3884375  PMID: 24426975
19.  NaAg2Mo3O9AsO4  
The title compound, sodium disilver arsenatotrimolybdate, Na0.93 (1)Ag2.07 (1)Mo3AsO13, was prepared by a solid-state reaction. In the crystal structure, isolated AsO4 tetra­hedra share corners with groups of three edge-sharing MoO6 octa­hedra. This arrangement leads to the formation of anionic 1 ∞[Mo3AsO13]n ribbons extending parallel to [100]. The three metal sites show occupational disorder by AgI and NaI cations, each with a different Ag:Na ratio. The metal cations are situated in the space between the ribbons and are surrounded by terminal O atoms of the ribbons in the form of distorted MO7 polyhedra (M = Ag, Na) for distances < 3.0 Å. The title compound shows weak ionic conductivity. Structural relationships between different compounds in the quaternary systems M–Sb–P–O, M–Nb–P–O and M–Mo–As–O (M is Ag or an alkali metal) are also discussed.
doi:10.1107/S160053681003463X
PMCID: PMC2983299  PMID: 21587345
20.  Cs0.49NbPS6  
The quaternary thio­phosphate, Cs0.49NbPS6, caesium hexa­thio­niobiophosphate(V), has been synthesized by the reactive halide flux method. The title compound is isotypic with Rb0.46TaPS6 and is made up of a bicapped trigonal–biprismatic [Nb2S12] unit and a tetra­hedral [PS4] group. The [Nb2S12] units linked by the [PS4] tetra­hedra form infinite chains, yielding a three-dimensional network with rather large van der Waals gaps along the c axis in which the disordered Cs+ ions reside. The electrons released by the Cs atoms are transferred to the pairwise niobium metal site and there are substantial inter­metallic Nb—Nb bonding inter­actions. This leads to a significant decrease of the inter­metallic distance in the title compound compared to that in TaPS6. The classical charge balance of the title compound may be represented as [Cs+]0.49[Nb4.51+][P5+][S2−]4[S2 2−].
doi:10.1107/S1600536810052724
PMCID: PMC3050425  PMID: 21522512
21.  The lanthanum(III) molybdate(VI) La4Mo7O27  
Crystals of the ortho­rhom­bic phase La4Mo7O27 (lanthanum molybdenum oxide) were obtained from a non-stoichiometric melt in the pseudo-ternary system La2O3–MoO3–B2O3. In the crystal structure, distorted square-anti­prismatic [LaO8] and monocapped square-anti­prismatic [LaO9] polyhedra are connected via common edges and faces into chains along [010]. These chains are arranged in layers that alternate with layers of [MoO4] and [MoO5] polyhedra parallel to (001). In the molybdate layers, a distorted [MoO5] trigonal bipyramid is axially connected to two [MoO4] tetra­hedra, forming a [Mo3O11] unit.
doi:10.1107/S1600536809026415
PMCID: PMC2977117  PMID: 21583295
22.  Nb1.30Cr0.70S5: a layered ternary mixed-metal sulfide 
The new layered ternary sulfide, Nb1.30Cr0.70S5, niobium chromium penta­sulfide, is isostructural with the solid solution Nb1+xV1−xS5 and belongs to the FeNb3Se10 structure type. Each layer is composed of two unique chains of face-sharing [NbS8] bicapped trigonal prisms (m symmetry) and edge-sharing [MS6] (M= Nb, Cr) octa­hedra (m symmetry). One of the two metal sites is occupied by statistically disordered Nb and Cr atoms, with 0.3 and 0.7 occupancy, respectively. The chains are connected along the c axis, forming two-dimensional layers, which then stack on top of each other to complete the three dimensional structure. As a result, an undulating van der Waals gap is found between the layers.
doi:10.1107/S1600536808041585
PMCID: PMC2967842  PMID: 21581463
23.  Hexakis(2-amino-4-methyl­pyridine-κN 1)dioxidohexa-μ4-sulfido-hexa­copper(I)divanadium(V) 
The title compound, [Cu6V2O2S6(C6H8N2)6], is constructed from six CuS3N and two VOS3 distorted tetra­hedra, forming an octa­nuclear V/S/Cu cluster with C i symmetry. The geometry around the V atoms is slightly distorted tetra­hedral, while there are large distortions from ideal tetra­hedral geometry for the Cu atoms. Adjacent metal–metal distances range from 2.693 (1) to 2.772 (10) Å, indicating weak metal–metal inter­actions in the cluster.
doi:10.1107/S1600536808027165
PMCID: PMC2960477  PMID: 21201649
24.  Neodymium(III) molybdenum(VI) borate, NdBO2MoO4  
Single crystals of NdBO2MoO4 were obtained from a molybdenum oxide–boron oxide flux under an air atmosphere. The structure features double chains of edge- and face-sharing distorted [NdO10] bicapped square-anti­prisms, which are linked by rows of isolated [MoO4] tetra­hedra and by zigzag chains of corner-sharing [BO3] groups, all of them running along the b axis. The chains of [NdO10], chains of [BO3] and rows of [MoO4] groups are arranged in layers parallel to the bc plane.
doi:10.1107/S1600536811017806
PMCID: PMC3120577  PMID: 21754565
25.  Lithium europium(III) molybdate(VI), Li3.5Eu1.5(MoO4)4  
The title compound, Li3.5Eu1.5(MoO4)4, was prepared by solid-state reactions. The fundamental building units of the structure are LiO4 polyhedra (site symmetry ), distorted LiO6 polyhedra and MoO4 tetra­hedra, which are further inter­connected via corner-sharing O atoms. One site is occupied by both Li and Eu atoms in a substituent disordered manner (0.25:0.75), and the Li/Eu atoms are coordinated by eight O atoms in a distorted square-antiprismatic manner.
doi:10.1107/S1600536812000268
PMCID: PMC3274837  PMID: 22346790

Results 1-25 (266758)