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The previously unknown crystal structure of the basic lead nitrate Pb2(OH)3(NO3) has been determined using single-crystal X-ray diffraction data (Mo-Kα radiation, CCD area detector). The compound is orthorhombic, space groupImmm,witha= 8.314(2),b= 8.545(2),c= 17.210(3)Å(R1 = 2.78% for 940 ‘observed’ reflections with Fo > 4σ(Fo)). The layered structure contains a previously unknown cuboid [Pb8(OH)12]4+cluster and NO3groups. The study used crystals formed by anthropogenic processes on a medieval mine dump, probably involving black gunpowder used in the blasting of ore. Pb2(OH)3(NO3) is associated with a second nitrate, Pb13O8(OH)6(NO3)4, which was previously designated as “Pb3O3(OH)4(NO3)2” or “Pb3(OH)5(NO3)”. It is rhombohedral, space group, witha= 10.263(1),c= 25.454(5) Å, and a structure solution is in complete agreement with an independent single-crystal study by Liet al.(2001). Probable hydrogen bonds in Pb2(OH)3(NO3) are indicated. Reported data onclusters and lead hydroxide and oxide nitrates are summarized and discussed critically. The probable conditions of formation of the studied samples are evaluated.

Two new layered gallophosphate-oxalate materials have been prepared hydrothermally using ethylenediamine and oxalic acid as structure-directing agents. The compounds (C 2 N 2 H 1 0 ) 2 [Ga 2 (C 2 O 4 ) 2 (HPO 4 ) 3 ].H 2 O 1 and (C 2 N 2 H 1 0 ) 3 -[Ga 4 (C 2 O 4 ) 4 (HPO 4 ) 4 (H 2 PO 4 ) 2 ] 2 are closely related, consisting of anionic double chains built of alternating pairs of GaO 6 and HPO 4 polyhedra. These double chains are linked via bridging HPO 4 or H 2 PO 4 tetrahedra to form corrugated layers containing eight-membered rings. The oxalate group acts as a bidentate ligand to each of the GaO 6 octahedron. The corrugated layers are held together by strong to weak hydrogen-bonding interactions between oxalate groups, water and diprotonated ethylenediamine molecules, and the framework components. The compounds were characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and infrared and Raman spectroscopy. Crystal data for 1: monoclinic, space group P2 1 /c (No. 14), a = 6.355(1) A, b = 39.362(8) A, c = 9.249(2) A, β = 106.7(1)°, Z= 2. Crystal data for 2: triclinic, space group P1 (No. 2), a = 8.730(1) A, b = 11.575(1) A, c = 11.696(1) A, a = 115.12(1)°, β = 90.07(1)°, y = 111.23(1)°, Z = 2.

The crystal structure of synthetic carlinite, Tl 2 S, was re-determined by single crystal and powder X-ray diffraction methods. The cell parameters obtained from Rietveld refinement are a =12.150(2) A, c =18.190(4) A, V =2325.5(7) A 3 . A single crystal data refinement proved Tl 2 S crystallizing in the trigonal space group R 3 with M =440.8gmol −1 , Z =27, R =0.076, and w R =0.145. The atomic arrangement found is that of a strongly deformed anti -CdI 2 type, but the deformation is clearly different from that given by previous workers. In the five crystallographically different STl 6 octahedra the S–Tl distances vary between 2.82 and 3.09A, the Tl–Tl edges between 3.52 and 4.58A. The common features of these octahedra are (i) each one with a definitely smaller vs larger Tl 3 face in trans -position, both faces parallel or sub-parallel (00.1), and (ii) each three shorter and longer S–Tl distances to the atoms of the larger and smaller Tl 3 faces, respectively. The Tl–Tl contacts between different Tl 2 S sheets are on the average definitely shorter than the ones within the sheet and they can be smaller than the Tl–Tl contacts in the small Tl 3 faces of the STl 6 octahedra. The atomic arrangement indicates that the single electron pairs of the monovalent Tl atoms are not arranged all parallel to the z -axis, as one would expect for Tl 2 S with an ideal anti -CdI 2 structure. The surrounding of the S atoms resembles that of one-third of the Cl atoms in yellow InCl. The absorbance of Tl 2 S is very low at wave numbers approximately −1 .

Ammonium di­(zinc, gallium) bis­(phosphate), (NH4)(Zn,Ga)2(PO4)2, has a zeolite-like open-framework structure. It contains channels of four- and eight-membered rings of alternating tetrahedra of (Zn,Ga)O4 (Zn:Ga ≃ 1:1) and PO4, in which the tetrahedra are connected via corners. The NH4+ cations are located in the channels and provide weak hydrogen bonds to the framework O atoms. The average (Zn,Ga)—O bond lengths of the two non-equivalent (Zn,Ga)O4 tetrahedra are 1.863 and 1.870 A. All atoms are in general positions. The compound is isostructural with K(CoII,Al)2(PO4)2 and [(NH4)x(NH3)0.5−x]CoxAl1−xPO4 (x = 0.38). Single-crystal Raman and IR spectra are discussed.

The crystal structure of arsentsumebite, ideally, Pb2Cu[(As, S)O4]2(OH), monoclinic, space group P21/m, a = 7.804(8), b = 5.890(6), c = 8.964(8) A, β = 112.29(6)°, V = 381.2 A3, Z = 2, dcalc. = 6.481 has been refined to R = 0.053 for 898 unique reflections with I> 2σ(I). Arsentsumebite belongs to the brackebuschite group of lead minerals with the general formula Pb2 Me(XO4)2(Z) where Me = Cu2+, Mn2+, Zn2+, Fe2+, Fe3+; X = S, Cr, V, As, P; Z = OH, H2O. Members of this group include tsumebite, Pb2Cu(SO4)(PO4)(OH), vauquelinite, Pb2Cu(CrO4)(PO4)(OH), brackebuschite, Pb2 (Mn, Fe)(VO4)2(OH), arsenbracke buschite, Pb2(Fe, Zn)(AsO4)2(OH, H2O), fornacite, Pb2Cu(AsO4)(CrO4)(OH), and feinglosite, Pb2(Zn, Fe)[(As, S)O4]2(H2O). Arsentsumebite and all other group members contain M = M–T chains where M = M means edge-sharing between MO6 octahedra and M–T represents corner sharing between octahedra and XO4 tetrahedra. A structural relationship exists to tsumcorite, Pb(Zn, Fe)2(AsO4)2 (OH, H2O)2 and tsumcorite-group minerals Me(1)Me(2)2(XO4)2(OH, H2O)2.

The crystal structures of bismutocolumbite, (Bi 0 . 9 9 Sb 0 . 0 1 )(Nb 0 . 7 9 Ta 0 . 2 1 )O 4 (I) and stibiocolumbite, Sb(Nb 0 . 6 7 Ta 0 . 3 3 )O 4 (II) were established from X-ray single crystal diffraction; I, orthorhombic, space group Pnna, a = 5.668(1) A, b = 11.725(2) A, c = 4.971(1) A, V = 330.4 A 3 , Z = 4, d c a l c . = 7.726, d o b s . = 7.17-7.56g/cm 3 , F(000) = 614, R = 0.025 for 820 unique reflections with I>2σ(I); II, orthorhombic, space group Pna2 1 a = 5.557(1) A, b = 4.932(1) A, c = 11.808(2) A, V = 323.6 A 3 , Z = 4, dean = 6.316, F(000) = 538, R = 0.023 for 1437 reflections with I>2σ(I). In both structures (Nb,Ta) atoms have octahedral coordination. In I Bi-O distances within distorted octahedron range from 2.126 to 2.738 A; (Nb,Ta)-O distances are between 1.852-2.148 A, in II Sb-O distances range from 2.008 to 2.619 A within distorted pseudotrigonal bypiramid; (Nb,Ta)-O distances are between 1.848 - 2.085 A. Both structures contain sheets of corner-linked (Nb,Ta)O 6 -octahedra separated by significantly distorted BiO 6 (SbO 5 )-polyhedra with four shorter distances opposite to the lone-pair electrons of Bi 3 + (Sb 3 + ). The repulsive forces between lone-pair electrons and the O atoms lead to the distortion of (Nb,Ta)O 6 octahedra in the stibiotantalite structure type. Two shortest bonds (Nb,Ta)-O(1) = 1.852 A in I as well as (Nb,Ta)-O(4) and -O(3) = 1.848 and 1.891 A, respectively, in II occur with ligands which are oriented in the direction of the lone-pair electrons of Bi 3 + (Sb 3 + ) and which form the elongated bonds Bi-O(1) = 2.738 A in I and Sb-O(3) = 2.619 A and Sb-O(4) = 3.012 A in II. The structures of I and II with a close packing indices (CPI) of 54 and 55, respectively, can not be considered as atomic ones in contrast to some other ABO 4 oxides with 6-fold coordination of cations, namely wolframite (Fe,Mn) [ 6 ] W [ 6 ] O 4 (CPI = 68) and rutile-like CrVO 4 (CPI = 74). The structural transitions (Pna2 1 to Pnna) in (Bi,Sb)(Nb,Ta)O 4 series should be considered as a function of chemical composition, temperature and pressure.

Large single crystals of optical quality and with dimensions up to 50 mm of double salts of the type X[C(NH2)3] Zr(N(CH2COO)3)2 ⋅ y H2O (X = Rb, Tl, NH4, Cs, CH3NH3) have been grown from aqueous solutions. They crystallize in the space group P21 and exhibit quasi-isotypic structures. Complete elastic and thermoelastic tensors have been derived from ultrasonic resonances of plane-parallel plates. In addition, thermal expansion, pyroelectric, dielectric and piezoelectric properties have been measured. The maximum longitudinal piezoelectric effects d 222 exceed d 111 of α-quartz roughly by a factor of 7. The pyroelectric constants π 2 surmount π 3 of tourmaline by about a factor of 9. The structural and physical properties are closely related to those of the constituent salts.

New sulfamates KLi(NH2SO3)2, RbLi ⋅ (NH2SO3)2 and CsLi(NH2SO3)2 were prepared from non-stoichiometric (ratio Li: Me = 3:1) aqueous solutions of LiNH2SO3 and MeNH2SO3 (Me = K, Rb, Cs) at room temperature. Large single crystals of KLi(NH2SO3)2 were grown from these solutions by controlled lowering of the temperature between 293 K and 288 K. The crystal structures were investigated using single-crystal X-ray diffraction methods. KLi(NH2SO3)2: space group P21, Z = 2, a = 5.196(1) Å, b = 8.475(1) Å, c = 8.868(1) Å, β = 105.05(1)°, T meas. = 293 K, R1 = 0.026; RbLi(NH2SO3)2: space group P1̅, Z = 4, a = 7.844(1) Å, b = 9.804(1) Å, c = 10.825(1) Å, α = 108.77(1)°, β = 93.29(1)°, γ = 98.64(1)°, T meas. = 293 K, R1 = 0.033; CsLi(NH2SO3)2 : space group P1̅, Z = 2, a = 5.535(1) Å, b = 7.877(1) Å, c = 9.857(1) Å, α = 74.07(1)°, β = 76.33(1)°, γ = 87.07(1)°, T meas. = 200 K; R1 = 0.023. The common feature of the three crystal structures are alternating layers of Me+ and lithium cations together with anionic [NH2SO3]– tetrahedra. Li+ coordination polyhedra and [NH2SO3]– anions, linked via common corners, form one type of these sheets. Additionally, these layers are stabilized by hydrogen bonds. Me+ coordination polyhedra are linked to each other and to the above mentioned layers by common corners and edges. RbLi(NH2SO3)2 and CsLi(NH2SO3)2 possess similar structures. Generally, the observed interatomic distances and angles agree with crystal chemical expectations. Differential scanning calorimetry measurements showed that KLi(NH2SO3)2 undergoes a first-order structural phase transition at 401 K and melts at 423 K. Between 153 K and 423 K no indications of further phase transitions were observed. In addition, the refractive indices and the tensor of thermal expansion were measured. Further, the elastic and thermoelastic constants of KLi(NH2SO3)2 were determined from ultrasonic resonant frequencies of thick plane-parallel plates and their shift upon variation of temperature, respectively. The elastic behaviour of KLi(NH2SO3)2 is similar to the average elastic properties of LiNH2SO3 and KNH2SO3.

Batiferrite, ideally Ba[Ti2Fe10]O19, was found in the Quaternary volcanic rocks near Udersdorf, Graulai, and Altburg, western Eifel area, Germany. The new mineral typically occurs as euhedral platy grains in cavities of melilite- and leucite-nephelinite basalts. Associated minerals are hematite, magnetite, titanite, gotzenite, clinopyroxene, nepheline, and biotite. It exhibits a hexagonal tabular habit flattened on {0001}, diameter 0.5–1 mm, thickness 20–125 μm, and {10&1macr;3}, {10&1macr;0} as observable forms. The mineral is opaque, of black color with submetallic lustre, and shows a ferrimagnetic behavior. VHN50 is 793 with a range of 710–841 from ten indentations. The quantitative reflectance measurements of Ro/Re on oriented grains in air and oil immersion, respectively, are [%]: for 470 nm 22.1/20.1 and 8.4/7.1, for 546 nm 21.0/19.4 and 7.8/6.6, for 589 nm 20.2/18.8 and 7.4/6.3, and for 650 nm 19.3/18.3 and 6.8/5.9. The bireflectance is distinct (air) to weak (oil), and parallel (0001) a moderate anisotropy with straight extinction can be observed. Typical microprobe analyses give [wt%] K2O 0.28–0.33, Na2O 0.17–0.20, SrO 0.46–0.55, BaO 11.80–12.17, MgO 1.27–1.47, Al2O3 0.31–0.33, TiO2 13.11–13.63, MnO 2.38–2.57, Fe2O3 61.36–63.12, FeO 5.49–5.86 (Fe3+/Fe2+ calculated for charge compensation), which is equivalent to (Ba0.84Na0.06K0.06Sr0.05)1.01(Fe8.48 3+Fe0.86 2+Ti1.82Mg0.37Mn0.37Al0.06)11.96O19 as the average composition based on 19 oxygen atoms. Batiferrite is a magnetoplumbite-type mineral with hexagonal symmetry, space group P6 3 /mmc (no. 194), a = 5.909(1) A, c = 23.369(4) A, V = 706.6(2) A3, Z = 2, and a calculated density of 5.016 gcm−3. The structure was refined to R1 = 0.031 for 278 unique reflections with Fo 2 > 4σ (Fo 2) and R1 = 0.079 for all 452 unique observations using single crystal X-ray data. The strongest reflections of the X-ray powder diffraction pattern are [d obs, I/Io, (hkl)]: 2.631, 100, (114); 2.799, 80, (107); 1.478, 70, (220); 2.429, 60, (203); 1.672, 50, (217). The new mineral is comparable to the other Ba containing magnetoplumbite-type minerals haggertyite and hawthorneite, the iron content, however, is much higher and in the range of magnetoplumbite. The large cation site (A) is dominated by Ba, and four of the five remaining crystallographic cation sites in the structure are dominated by Fe (M1, 2, 3, 5), the octahedrally coordinated M4-site is dominated by Ti. No oxygen vacancy on the O3-site like in plumboferrite can be observed. Batiferrite is named for its main chemical composition and the relationship to the M-type hexaferrites (polytype 5H).

Brandholzite, a new magnesium antimony hydroxide hydrate mineral, Mg(H2O)6[Sb(OH)6]2, has been discovered in Au-Sb-Quartz veins of the former mining district of Brandholz-Goldkronach, Fichtelgebirge, Germany. The new mineral is associated with stibnite and antimony-ochers and forms colorless, platelike crystals up to ~1 mm in size. Natural as well as synthetic samples obtained by slow evaporation of an aqueous solution exhibit {1010} twinning, leading to a pronounced 31m pseudo-symmetry. The crystal structures of brandholzite and its synthetic analogue were investigated using single crystal X-ray CCD data: trigonal, space group P 3, Z = 6, a = 16.119(1) A, c = 9.868(1) A, R 1 = 0.034 for 14788 F o > 4σ( F o) (brandholzite), and a = 16.113(1) A, c = 9.868(1) A, R 1 = 0.029 for 16624 F o > 4σ( F o) (synthetic analogue) and 525 variable parameters each. The structures are isotypic with bottinoite, Ni(H2O)6[Sb(OH)6]2, and are built up by nearly regularly shaped, isolated Mg(H2O)6 and Sb(OH)6 octahedra which are interconnected by hydrogen bonds only. The strongest lines in the powder pattern are [ d -value (A), I , hkl ]: 4.636, 100, (300); 3.392, 70, (302); 4.946, 50, (002); 2.356, 40, (332). At 589 nm, the mineral is optically uniaxial negative with refractive indices n ω = 1.570(2) and n e = 1.569(2). The crystal structure of the pseudoisotypic synthetic compound Co(H2O)6[Sb(OH)6]2 was also investigated: trigonal, space group P 3, a = 16.105(1), c = 9.851(1), Z = 6, R1 = 0.051 for 13516 reflections with F o > 4σ( F o) and 525 parameters. Compared to the Mg-antimonates and bottinoite, a significant rotation of some Sb(OH)6 octahedra is observed in Co(H2O)6[Sb(OH)6]2.

Large single crystals of ammonium bis(nitrilotriacetato)zirconate, (NH4)2[Zr{N(CH2COO)3}2] (to be written (NH4)2[Zr(NTA)2), were grown. Linear optical properties were measured (indices of refraction and transparency range) and the phase matching conditions for second harmonic generation process were determined. Crystal structures of the zirconate and the isomorphic hafnate were solved from single crystal X-ray diffraction data (P31,2; Z= 3; Zr: a= 9.582(1)Å, c= 16.611(4)Å, Hf: a= 9.5846(5)Å, c=16.5920(8)Å and the geometry of the complex groups [Zr(NTA)2]2- and [Hf(NTA)2]2- was analysed.

The new members of the series of 2,5-disubstituted DCNQIs, 1d (Cl/OMe), 1e (Br/OMe), 1j (Cl/I), 1k (Br/I), 1l (I/I), form conducting charge-transfer complexes with TTF (tetrathiofulvalene) which are comparable to known DCNQI/TTFs. From these DCNQIs highly conducting radical-anion salts [2-X, 5-Y-DCNQI]2M (M = Li, Na, K, NH4, Tl, Rb, Ag, Cu) can also be prepared either from the DCNQIs and MI (not AgI), on a metal wire (Ag, Cu), or by electrocrystallization (M = Tl, Ag,Cu). For better crystals a method using periodical switching between reduction and partial oxidation has been developed. With CF3 (large, strongly electron-attracting) as the substituent in DCNQIs 1m (OMe/CF3) and 1n (Me/CF3), conducting TTF complexes remain whereas only 1n yields an insulating copper salt. DCNQI–Cu salts with high conductivities are obtained with alloys containing two or three different DCNQIs. The temperature-dependent conductivities of DCNQI–M salts (other than copper) are similar to those of metal-like semiconductors. All new DCNQI–Cu salts are metallic [M] down to low temperatures, except [1d (Cl/OMe)]2Cu which undergoes a sharp phase transition to an insulating state[M I]. By variation of the ligands or their ratios in conducting alloys of DCNQI–Cu salts temperature-dependent conductivities can be tuned from M I to M. In addition, alloying three ligands produced for the first time a radical salt with temperature-independent conductivity from 5 to 300 K. Most remarkably, alloys of the type [(2,5-Me2DCNQI)m] Cu/[{2,5-(CD3)2-DCNQI}n]2Cu which exhibit a sharp M I phase transition on further cooling reenter the conducting state by an I M transition, with changes of ca. 108 Scm−1 both ways. For the first time in the field of organic metals crystal structures of DCNQI–copper salts have been determined by X-ray powder diffraction methods and refined by Rietveld analysis. Unit cell data, coordination angles and distances of the π planes are in excellent agreement with the single-crystal X-ray data. However, bond lengths and angles of the ligands are to be less accurate. This powder method proves to be most valuable if only microcrystalline material is available.

A sample of the zeolite paulingite from the locality Vinarická Hora was investigated by means of chemical, thermal, powder and single crystal X-ray methods. The fully transparent, colourless to pale yellow crystals exhibit the form {110} and occur together with phillipsite. The chemical composition is (Ca2.57K2.28Ba1.39Na0.38)(Al11.55Si30.59O84)·27H2O, Z = 16 with minor amounts of Mg (−3, and the observed refractive index is 1.482(2). The dehydration behaviour is characterized by a main weight loss from 24–190°C (−11.2 wt.%, ≅ 21H2O) and a minor weight loss from 190–390°C (−3.1 wt.%, ≅ 6H2O). The rehydration capability was proven up to 150°C. The dehydration process during the main weight loss is accompanied by a reduction of the cell volume of 11%. The refined lattice parameters of the X-ray powder data are a a = 35.1231 (5) Å and a = 33.7485(8) Å of an untreated and a dehydrated sample, respectively. A breakdown of the paulingite structure can be observed while the remaining water content decomposes. The single crystal X-ray refinement of this chemically different sample material derived three main cation positions, which are inside a so called paulingite or π-cage (Ca), between 8-rings of neighbouring π-cages (Ba), and in the centre of the non-planar 8-rings of the γ-cage (K). Further partially occupied cation positions (Ca,Na) were located in the planar 8-rings of the α- and γ-cages. No positions within the double 8-membered rings were detected. The water is localized around the main cation positions and in three clusters of partially occupied sites.

The new mineral ternesite, Ca5(SiO4)2SO4, has been found at the Ettringer Bellerberg near Mayen, Eifel, Germany. The crystal structure, already known from the synthetic analogue, was refined from single crystal X-ray data: orthorhombic, space group Puma with a= 6.863(1)A, b=15.387(2) A, c=10.181(1) A Z=4, R=0.058, Rw=0.046 for 820 unique reflections with F0> 3σ(F0) and 96 variable parameters. The strongest peaks in the powder pattern are (d-value (A),I, hkl): 2.830, 100, (033)/2.853, 63, (230)/2.565, 55, (060)/3.198, 42, (132)/1.892, 39, (035) + (125). The mineral is optically biaxial negative with refractive indices nx = 1.630(1) (parallel [100]), ny = 1.637(2) (parallel [001]), and nz = 1.640(1) (parallel [010]). The optical angle 2Vx was measured as 63.5(5)°.

The structure of Al2GeO4(OH)2 [C2/c; a = 5.4197(3) Å, b = 8.2464(3) Å, c = 9.3187(3) Å, β = 110.933(3); Z = 4] was refined by X-ray Rietveld methods. It contains GeO4 tetrahedra having all four O atoms in common with an AlO2OH framework built from AlO4(OH)2 octahedra sharing three edges. The H atom could be located only approximately. The coordinations of the atoms are mostly as in topaz, Al2SiO4(F,OH)2, and its synthetic OH endmember, but the arrangement of the oxygen atoms is that of a distorted cubic close-packing, while in topaz it is based on a close-packing of the type ABAC.

A hitherto unknown TI-sulfosalt, containing antimony and arsenic, was discovered by ore microscopy (including quantitative reflectance measurements) and electron microprobe analysis in samples from the Allchar TI-Sb-As sulfide ore deposit (Macedonia). The chemical formula is TI5Sb9(As,Sb)4S22, X-ray single crystal and powder diffration data gave the lattice parametersα o = 7.393(4) A, b0 = 8.707(2) A, co = 17.584(3) A,α = 103.81(1)°,β = 91.79(1)°,γ = 109.50(1)°; space group $$P\bar 1$$ , Z = 1. The new mineral and the new mineral naine “jankovieite” have been approved by the IMA/CNMMN.

The X-ray structure analysis of the title compound, chloro[1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazin-4-ium-1-yl)-3-quinolinecarboxylate-kappa(2)O(3),O(4)](1,10-phenanthroline-kappa(2)N,N')copper chloride dihydrate, [CuCl(C(17)H(18)FN(3)O(3))(C(12)H(8)N(2))]Cl x 2H(2)O or [CuCl(cfH)(phen)]Cl x 2H(2)O, where cfH is 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazin-4-ium-1-yl)-3-quinolinecarboxylate and phen is 1,10-phenanthroline, shows that the geometry around the Cu ion is a slightly distorted square pyramid. Two O atoms of the carbonyl and carboxyl groups of ciprofloxacin and two N atoms of 1,10-phenanthroline are coordinated to the metal centre in the equatorial plane, and a Cl(-) ion is coordinated at the apical position. Extensive intermolecular hydrogen bonding produces a supramolecular structure that consists of alternating six- and 12-membered rings.

The new mineral orschallite, Ca3(SO3)2SO4 · 12H2O, was found at the Hannebacher Ley near Hannebach, Eifel, Germany. Crystal structure analysis of the mineral, chemical analysis and water determination on synthetic material gave the composition Ca3(SO3)2SO4 · 12H2O. The mineral crystallizes in space group\(R\bar 3c\) with a = 11.350(1), c = 28.321(2) A, V = 3159.7 A3, Z = 6, Dc = 1.87 Mg/m3, Dm = 1.90(3) Mg/m3. It is uniaxial positive with the optical constantsω = 1.4941,ɛ = 1.4960(4). The strongest lines in the powder pattern are (d-value (A), I, hkl) 5.73, 100, 1 0 4/8.11, 80, 0 1 2/2.69, 80, 3 0 6/3.63, 60, 1 1 6/3.28, 40, 3 0 0. Refinement of the crystal structure led to a weighted residual of Rw = 0.043 for 600 observed reflections with I > 2σ(I) and 52 variable parameters.

Nickenichite is a new mineral found close to the village of Nickenich at the Nickenicher Sattel, Eifel, Germany. The chemical composition is NaxCayCuz(Mg, Fe, Al)3(AsO4)3, x ≈ 0.8, y ≈ 0.4, ≈ 0.4 and was derived by means of electron microprobe analyses and by a crystal structure investigation. The latter was determined from single-crystal X-ray data:a = 11.882(4)A,b = 12.760(4)A,c = 6.647(2)A,β = 112.81(2)°, space group C2/c,Z = 4;R = 0.053 andRw = 0.033 from 984 observed data and 102 free variables. Nickenichite is structurally related to the minerals o'danielite and johillerite. The two crystallographically different octahedrally coordinated cation positionsMe = (Mg, Fe, Al) have averageMe-O distances of 2.108 A and 2.056 A, octahedra share edges to form zig-zag chains in\([10\bar 1]\); the chains are interconnected by AsO4 tetrahedra. In addition the compound is characterized by partially occupied Na[4+4], Ca[6+2] and Cu[4] positions.

The new mineral bellbergite, (K, Ba, Sr)2Sr2Ca2(Ca, Na)4Al18Si18O72 · 30H2O, has been found in Ca-rich xenoliths at the Bellberg volcano near Mayen, Eifel, Germany. It occurs as well formed bipyramids with a length up to 0.3 mm. Possible space groups are P63/mmc, P62c and P63mc with a = 13.244(1) A, c = 15.988(2) A, V = 2429 A3, Z = 1. The density is: Dm, = 2.20(2) Mg/m3, Dc = 2.19 Mg/m3. The empirical formula based on 72 oxygen atoms is: Ba0.26Na0.72K1.33Sr2.36Ca5.32Al17.55Si18.36O72 · 30H2O. The mineral is uniaxial negative with ω = 1.522(2) and e = 1.507(2) (λ = 589 nm). The strongest lines in the X-ray powder pattern are (d (A), I, hkl): 3.80 (100) (300, 212, 104), 6.58 (80) (102), 2.95 (70) (312, 214), 2.21 (70) (330), 2.70 (50) (402), 2.50 (50) (410, 314), 1.83 (50) (416). The crystal structure corresponds to the zeolite structure type EAB.

The title compound, dibarium digadolinium(III) tetra­silicate, crystallized from a molybdate-based flux. It represents a new structure type and contains finite zigzag-shaped C 2-symmetric Si4O13 chains and Gd2O12 dimers built of edge-sharing GdO7 polyhedra. The [9+1]-coordinated Ba atoms are located in voids in the atomic arrangement. All atoms are in general positions except for one O atom, which lies on a twofold axis. The structure is compared with those of the few other known tetra­silicates.

A novel layered zinc phosphate, [N(2)C(6)H(12)](2)[Zn(7)H(3)(HPO(4-x))(5)(PO(4))(3)]H(2)O, with unique 10-membered-ring ellipsoidal channels running perpendicularly to ladder-shaped tetrahedral layers, has been synthesized ionothermally via in situ generation of 1,4-diazabicyclo[2.2.2]octane.

Prismatic colourless crystals of the two novel, isotypic title compounds were obtained by the flux growth technique. The crystal structures have been determined from single-crystal intensity data in space group R 3 with a = 28.819(4) / 28.799(4), c = 13.916(3) / 13.864(3) A, V = 10009(3) / 9958(3) A3, Z = 6, R (F) = 4.99 / 6.44%, respectively. They represent a novel structure type with microporous character. The framework is built from six-membered silicate rings (approximate UDUDUD orientation) containing isolated YO6 octahedra and compressed “six-membered rings”, which in fact build a spiral of corner-sharing SiO4 tetrahedra. Approximately parallel to [111] run two different irregular channels hosting the Rb/Cs and Rb atoms. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Four different rubidium metal molybdates and Rb 2 Mo 4 O 13 have been synthesised by flux growth and their crystal structures were determined from single-crystal X-ray diffraction data. The compound Rb 5 Fe(MoO 4 ) 4 represents a novel and unusual structure type based on isolated Fe 2 Mo 8 O 32 building blocks (with a central Fe 2 O 8 dimer composed two edge-sharing square pyramids in an up-down arrangement) linked by Rb + cations (Cmca, a = 18.355(4), b = 10.487(2), c = 39.303(3) A, V = 7566(4) A 3 , R(F) = 3.46%, Z = 16). Rb 5 In(MoO 4 ) 4 is characterised by a decorated krohnkite-like octahedral-tetrahedral chain structure (P2/c, a=11.391(2), b = 7.983(2), c = 11.100(2) A, β = 113.74(3)°, V = 924.0(3) A 3 , R(F) = 2.27%, Z = 2). It is isotypic with Rb 5 Er(MoO 4 ) 4 . The two compounds RbFe(MoO 4 ) 2 and RbSc(MoO 4 ) 2 , both crystallise in KAl(MoO 4 ) 2 -type structures in space group P3ml, with a = 5.673(1)/5.789(1), c = 7.495(2)/7.578(2) A, V = 208.89(8)/219.93(8) A 3 , R(F) = 1.69/1.26%, respectively, Z = 1. The simple Rb molybdate Rb 2 Mo 4 O 13 is triclinic and isotypic with K 2 Mo 4 O 13 and the triclinic modification of (NH 4 ) 2 Mo 4 O 13 . It has space group P1, with a = 8.259(2), b = 8.402(2), c = 10.274(2) A, a = 104.56(3)β = 106.41(3), y = 109.90(3)°, V= 593.4(2) A 3 , R(F) = 2.20%, Z = 2. The different connectivities within the structures and the role of the Rb atoms are discussed. The topologies and relative stabilities of M 2 Mo 4 O 13 (M= (NH 4 ), K, Rb, Cs, Tl) compounds and their structure types are briefly reviewed.

Aluminium borate 9Al 2 O 3 .2B 2 O 3 (A 9 B 2 ) and Cr 3+ -rich and A 9 B 2 (≃10 wt% Cr 2 O 3 ) were synthesized from oxide powders by solid state reactions. The fractional atomic coordinates determined from single crystal diffraction data agree comparatively well with those obtained by the Rietveld method using powder X-ray diffraction data. The crystal structure of A 9 B 2 is similar to the structures of sillimanite, mullite and andalusite. The main structural units common to all four phases are the infinite chains of edge-sharing AlO 6 -octahedra running parallel to c. Chromium incorporation causes an expansion of the structure. Refinement of occupancy factors has shown the preference of Cr 3+ for the octahedrally coordinated Al (1)-position

Six acentric tartrates and tartrato-antimonates have been investigated by means of X-ray powder diffraction. Single crystals were obtained by evaporation from aqueous solutions. The compounds have attracted attention because of their electrostrictive and electro-optical effects. Complete crystal data for the six compounds are reported. X-ray powder diffraction patterns for Rb2C4H4O6and Ca [Sb2{C4H2O6}2]·2H2O are given.

New conducting CT-complexes and radical anion salts are presented derived from substituted N,N'-dicyanoquinonediimine (DCNQI's), 2,5-Bis(cyanimino)-2,5-dihydrothieno[3,2-b]thiophenes (DCNTT's) and dicyanazobenzenes (DCNAB's), a new type of acceptor.

BaY2Si3O10, barium diyttrium trisilicate, is a new silicate grown from a molybdate-based flux. The structure is based on zigzag chains, parallel to [010], of edge-sharing distorted YO6 octa­hedra, linked by horseshoe-shaped trisilicate groups and Ba atoms in irregular eight-coordination. The layered character of the structure is caused by a succession of zigzag chains and trisilicate groups in planes parallel to (\overline{1}01). The Ba atoms occupy narrow channels extending parallel to [100]. The mean Y—O, Si—O and Ba—O bond lengths are 2.268, 1.626 and 1.633, and 2.872 A, respectively. The two symmetry-equivalent terminal SiO4 tetra­hedra in the Si3O10 unit adopt an eclipsed conformation with respect to the central SiO4 tetra­hedron; the Si—O—Si and Si—Si—Si angles are 136.35 (9) and 96.12 (4)°, respectively. One Ba, one Si and two O atoms are located on mirror planes; all remaining atoms are in general positions. The geometry of isolated trisilicate groups in inorganic compounds is briefly discussed.

Single crystals of (Ag 3 Hg)VO 4 (I), (Ag 2 Hg 2 ) 3 (VO 4 ) 4 (II), AgHgVO 4 (III), and (Ag2Hg2)2(HgO 2 )(As04)2 (IV) were grown under hydrothermal conditions (250 °C, 5 d) from starting mixtures of elementary mercury, silver nitrate, ammonium vanadate, and disodium hydrogenarsenate, respectively. All crystal structures were determined from X-ray diffraction data, and their chemical compositions were confirmed by electron microprobe analysis. I crystallizes in the tillmannsite structure, whereas II-IV adopt new structure types: (I) I4, Z= 2, a = 7.7095(2) ´ο, c = 4.6714(2) A, 730 structure factors, 24 parameters, R[F 2 > 2σ(F 2 )] = 0.0365; (II) I42d, Z = 4, a = 12.6295(13) A, c = 12.566(3) A, 1524 structure factors, 55 parameters, R[F 2 > 2σ(F 2 )] = 0.0508; (III) C2, Z = 4, a = 9.9407(18) A, b = 5.5730(8) A, c = 7.1210(19) A, β = 94.561(10)°, 1129 structure factors, 48 parameters, R[F 2 > 2σ(F 2 )] = 0.0358; (IV) P31c, Z = 2, a = 6.0261(9) A, c = 21.577(4) A, 1362 structure factors, 52 parameters, R[F 2 > 2σ(F 2 )] = 0.0477. The most striking structural features of I, II, and IV are the formation of tetrahedral cluster cations (Ag 3 Hg) 3 + and (Ag 2 Hg 2 ) 4 + , respectively, built of statistically distributed Ag and Hg atoms with a metal-metal distance of about 2.72 A. The electronic structure of these clusters can formally be considered as two-electron-four-center bonding. The crystal structure of III differs from the protrusive structure types insofar as silver and mercury are located on distinct crystallographic sites without a notable metal-metal interaction >3.55 A. All crystal structures are completed by tetrahedral oxo anions XO 4 3 - (X = V V , As V ) and for IV additionally by a mercurate group, HgO 2 2 - .

Single crystals of Cs3A[B2(SCN)7] with A = Sr, Ba and B = Ag, Cu have been synthesized from aqueous solutions by the evaporation method. The complex thiocyanates are isostructural and crystallize in the tetragonal system with space group.Complete crystal data and optical data for the four compounds are reported. An X-ray powder diffraction pattern for Cs3Sr[Cu2(SCN)7] is given.

C 8 H 4 N 6 •C 10 H 12 S 4 cristallise dans P1 avec a=7,656, b=8,074, c=9,236 A, α=89,67, β=88,16, γ=62,58 o , Z=1; affinement jusqu'a R=0,036. Les systemes electroniques π des deux molecules organiques forment un empilement mixte avec la liaison double du second compose au-dessus un cycle benzene du premier compose a une distance intermoleculaire de 3,45 A

The structure of the layered noncentrosymmetric titanosilicate AM-1 (also known as JDF-L1, disodium titanium tetrasilicate dihydrate), Na4Ti2Si8O22·4H2O, grown as small single crystals without the use of organics, has been refined from single-crystal X-ray diffraction data. The H atom has been located for the first time, and the hydrogen-bonding scheme is also characterized by IR and Raman spectroscopy. All atoms are in general positions except for the Na, the Ti, one Ti-bound O, one Si-bound O and the water O atoms (site symmetries 2, 4, 4, 2 and 2, respectively).

A single-crystal X-ray study of dibarium nonatitanate, Ba2Ti9O20, yielded the triclinic space group P 1 with a=0.7471(1), b= 1.4081(2), c= 1.4344(2) nm, α=89.94(2)°, β= 79.43(2)°, γ= 84.45(2)°, V = 1.476 nm3 Z = 4, and Dx= 4.61 Mg/m3. A refinement of atomic coordinates and isotropic thermal parameters led to a residual of 0.03. The structure consists of hexagonally closest-packed layers of Ba and O atoms in the sequence (hch)3. All Ti atoms reside in octahedral interstices of this closest packing. The various Ti coordination octahedra share only edges and corners with each other. One-half of the Ba atoms is twelve-coordinated by oxygen atoms, the other half is eleven-coordinated.

The structure of trizinc diorthoborate is shown to crystallize in the centrosymmetric space group 12/e, and not in Ie as assumed by GARCIA-BLANCO and FAYOS (1968) who determined the structure originally. The new refinement yielded an R = 0.133 for 787 FobS, as compared to R = 0.132 achieved by the previous authors. The bond lengths and angles in the centrosymmetric structure agree well with values for comparable bonds in well determined structures, while the acentric structure exhibits some unusual distortions from the commonly accepted values.

A single-crystal X-ray study of dibarium nonatitanate, Ba2Ti9O20, yielded the triclinic space group P 1 with a=0.7471(1), b= 1.4081(2), c= 1.4344(2) nm, α=89.94(2)°, β= 79.43(2)°, γ= 84.45(2)°, V = 1.476 nm3 Z = 4, and Dx= 4.61 Mg/m3. A refinement of atomic coordinates and isotropic thermal parameters led to a residual of 0.03. The structure consists of hexagonally closest-packed layers of Ba and O atoms in the sequence (hch)3. All Ti atoms reside in octahedral interstices of this closest packing. The various Ti coordination octahedra share only edges and corners with each other. One-half of the Ba atoms is twelve-coordinated by oxygen atoms, the other half is eleven-coordinated.